diff --git a/Cargo.lock b/Cargo.lock
index 087328c888c..e5c566e5cc1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -379,7 +379,7 @@ dependencies = [
  "float-cmp",
  "futures-lite 2.5.0",
  "hashbrown 0.15.2",
- "icu_calendar",
+ "icu_calendar 1.5.2",
  "icu_casemap",
  "icu_collator",
  "icu_datetime",
@@ -389,7 +389,7 @@ dependencies = [
  "icu_locid_transform",
  "icu_normalizer",
  "icu_plurals",
- "icu_provider",
+ "icu_provider 1.5.0",
  "icu_segmenter",
  "indexmap",
  "indoc",
@@ -419,9 +419,9 @@ dependencies = [
  "thin-vec",
  "thiserror",
  "time",
- "tinystr",
+ "tinystr 0.7.6",
  "web-time",
- "writeable",
+ "writeable 0.5.5",
  "yoke",
  "zerofrom",
 ]
@@ -466,7 +466,7 @@ dependencies = [
  "icu_locid_transform",
  "icu_normalizer",
  "icu_plurals",
- "icu_provider",
+ "icu_provider 1.5.0",
  "icu_provider_adapters",
  "icu_provider_blob",
  "icu_segmenter",
@@ -1297,7 +1297,7 @@ dependencies = [
  "displaydoc",
  "ryu",
  "smallvec",
- "writeable",
+ "writeable 0.5.5",
 ]
 
 [[package]]
@@ -1543,10 +1543,10 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dff5e3018d703f168b00dcefa540a65f1bbc50754ae32f3f5f0e43fe5ee51502"
 dependencies = [
- "icu_calendar",
+ "icu_calendar 1.5.2",
  "icu_casemap",
  "icu_collator",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_datetime",
  "icu_decimal",
  "icu_experimental",
@@ -1556,7 +1556,7 @@ dependencies = [
  "icu_normalizer",
  "icu_plurals",
  "icu_properties",
- "icu_provider",
+ "icu_provider 1.5.0",
  "icu_segmenter",
  "icu_timezone",
 ]
@@ -1570,21 +1570,39 @@ dependencies = [
  "calendrical_calculations",
  "databake",
  "displaydoc",
- "icu_calendar_data",
  "icu_locid",
- "icu_locid_transform",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "tinystr",
- "writeable",
- "zerovec",
+ "tinystr 0.7.6",
+ "writeable 0.5.5",
+ "zerovec 0.10.4",
+]
+
+[[package]]
+name = "icu_calendar"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3689f3f720936703584298dce9711d8c68b7aecef258d0e1e2677ec3d9567ff6"
+dependencies = [
+ "calendrical_calculations",
+ "displaydoc",
+ "icu_calendar_data",
+ "icu_locale_core",
+ "icu_provider 2.0.0-beta1",
+ "tinystr 0.8.0",
+ "writeable 0.6.0",
+ "zerovec 0.11.0",
 ]
 
 [[package]]
 name = "icu_calendar_data"
-version = "1.5.0"
+version = "2.0.0-beta1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e009b7f0151ee6fb28c40b1283594397e0b7183820793e9ace3dcd13db126d0"
+checksum = "a113bfe4a5f0a4f9ab2f4ec5baac9f5cfab7c5ada910abf4b9ed4cfd066881cd"
+dependencies = [
+ "icu_locale",
+ "icu_provider_baked",
+]
 
 [[package]]
 name = "icu_casemap"
@@ -1594,13 +1612,13 @@ checksum = "9ff0c8ae9f8d31b12e27fc385ff9ab1f3cd9b17417c665c49e4ec958c37da75f"
 dependencies = [
  "databake",
  "displaydoc",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_locid",
  "icu_properties",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "writeable",
- "zerovec",
+ "writeable 0.5.5",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1609,10 +1627,10 @@ version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c41aa8d27817174c88860a3227fa5cc50cf2d915367f626d56f5711dd8a2e22a"
 dependencies = [
- "icu_collections",
+ "icu_collections 1.5.0",
  "toml 0.5.11",
  "wasmi",
- "zerovec",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1623,15 +1641,15 @@ checksum = "d370371887d31d56f361c3eaa15743e54f13bc677059c9191c77e099ed6966b2"
 dependencies = [
  "databake",
  "displaydoc",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_normalizer",
  "icu_properties",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
  "smallvec",
  "utf16_iter",
  "utf8_iter",
- "zerovec",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1645,7 +1663,20 @@ dependencies = [
  "serde",
  "yoke",
  "zerofrom",
- "zerovec",
+ "zerovec 0.10.4",
+]
+
+[[package]]
+name = "icu_collections"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "547ceba155a760830b848d9ae28183bc6bddf1b714ffc27bee1c7144f07229db"
+dependencies = [
+ "displaydoc",
+ "potential_utf",
+ "yoke",
+ "zerofrom",
+ "zerovec 0.11.0",
 ]
 
 [[package]]
@@ -1659,11 +1690,11 @@ dependencies = [
  "either",
  "elsa",
  "icu",
- "icu_calendar",
+ "icu_calendar 1.5.2",
  "icu_casemap",
  "icu_codepointtrie_builder",
  "icu_collator",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_datetime",
  "icu_decimal",
  "icu_experimental",
@@ -1674,7 +1705,7 @@ dependencies = [
  "icu_pattern",
  "icu_plurals",
  "icu_properties",
- "icu_provider",
+ "icu_provider 1.5.0",
  "icu_provider_adapters",
  "icu_provider_blob",
  "icu_segmenter",
@@ -1692,13 +1723,13 @@ dependencies = [
  "serde",
  "serde-aux",
  "serde_json",
- "tinystr",
+ "tinystr 0.7.6",
  "toml 0.5.11",
  "twox-hash",
  "ureq",
- "writeable",
- "zerotrie",
- "zerovec",
+ "writeable 0.5.5",
+ "zerotrie 0.1.3",
+ "zerovec 0.10.4",
  "zip",
 ]
 
@@ -1712,18 +1743,18 @@ dependencies = [
  "displaydoc",
  "either",
  "fixed_decimal",
- "icu_calendar",
+ "icu_calendar 1.5.2",
  "icu_decimal",
  "icu_locid",
  "icu_plurals",
- "icu_provider",
+ "icu_provider 1.5.0",
  "icu_timezone",
  "litemap",
  "serde",
  "smallvec",
- "tinystr",
- "writeable",
- "zerovec",
+ "tinystr 0.7.6",
+ "writeable 0.5.5",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1735,9 +1766,9 @@ dependencies = [
  "databake",
  "displaydoc",
  "fixed_decimal",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "writeable",
+ "writeable 0.5.5",
 ]
 
 [[package]]
@@ -1749,7 +1780,7 @@ dependencies = [
  "databake",
  "displaydoc",
  "fixed_decimal",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_decimal",
  "icu_locid",
  "icu_locid_transform",
@@ -1757,7 +1788,7 @@ dependencies = [
  "icu_pattern",
  "icu_plurals",
  "icu_properties",
- "icu_provider",
+ "icu_provider 1.5.0",
  "litemap",
  "log",
  "num-bigint",
@@ -1765,11 +1796,11 @@ dependencies = [
  "num-traits",
  "serde",
  "smallvec",
- "tinystr",
- "writeable",
+ "tinystr 0.7.6",
+ "writeable 0.5.5",
  "zerofrom",
- "zerotrie",
- "zerovec",
+ "zerotrie 0.1.3",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1781,10 +1812,48 @@ dependencies = [
  "databake",
  "deduplicating_array",
  "displaydoc",
- "icu_provider",
+ "icu_provider 1.5.0",
  "regex-automata 0.2.0",
  "serde",
- "writeable",
+ "writeable 0.5.5",
+]
+
+[[package]]
+name = "icu_locale"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f49d3c7f2dae0cd50d8b681a258e761eb714c9924f8222b7042118c0fb410649"
+dependencies = [
+ "displaydoc",
+ "icu_collections 2.0.0-beta1",
+ "icu_locale_core",
+ "icu_locale_data",
+ "icu_provider 2.0.0-beta1",
+ "potential_utf",
+ "tinystr 0.8.0",
+ "zerovec 0.11.0",
+]
+
+[[package]]
+name = "icu_locale_core"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e36332a8c93574b07598351bb479425282022341528ff521238fd4a48d143162"
+dependencies = [
+ "displaydoc",
+ "litemap",
+ "tinystr 0.8.0",
+ "writeable 0.6.0",
+ "zerovec 0.11.0",
+]
+
+[[package]]
+name = "icu_locale_data"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "222f29513408cc4572fce10bcadd05505c61ca1e30412416661e2fd464821c80"
+dependencies = [
+ "icu_provider_baked",
 ]
 
 [[package]]
@@ -1797,9 +1866,9 @@ dependencies = [
  "displaydoc",
  "litemap",
  "serde",
- "tinystr",
- "writeable",
- "zerovec",
+ "tinystr 0.7.6",
+ "writeable 0.5.5",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1812,10 +1881,10 @@ dependencies = [
  "displaydoc",
  "icu_locid",
  "icu_locid_transform_data",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "tinystr",
- "zerovec",
+ "tinystr 0.7.6",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1832,16 +1901,16 @@ checksum = "19ce3e0da2ec68599d193c93d088142efd7f9c5d6fc9b803774855747dc6a84f"
 dependencies = [
  "databake",
  "displaydoc",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_normalizer_data",
  "icu_properties",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
  "smallvec",
  "utf16_iter",
  "utf8_iter",
  "write16",
- "zerovec",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1860,7 +1929,7 @@ dependencies = [
  "displaydoc",
  "either",
  "serde",
- "writeable",
+ "writeable 0.5.5",
  "yoke",
  "zerofrom",
 ]
@@ -1874,9 +1943,9 @@ dependencies = [
  "databake",
  "displaydoc",
  "fixed_decimal",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "zerovec",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1887,13 +1956,13 @@ checksum = "93d6020766cfc6302c15dbbc9c8778c37e62c14427cb7f6e601d849e092aeef5"
 dependencies = [
  "databake",
  "displaydoc",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_locid_transform",
  "icu_properties_data",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "tinystr",
- "zerovec",
+ "tinystr 0.7.6",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1912,16 +1981,33 @@ dependencies = [
  "displaydoc",
  "erased-serde",
  "icu_locid",
- "icu_provider_macros",
+ "icu_provider_macros 1.5.0",
  "log",
  "postcard",
  "serde",
  "stable_deref_trait",
- "tinystr",
- "writeable",
+ "tinystr 0.7.6",
+ "writeable 0.5.5",
  "yoke",
  "zerofrom",
- "zerovec",
+ "zerovec 0.10.4",
+]
+
+[[package]]
+name = "icu_provider"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "201d2b3bc0bd9a7ad78a00af62374365dd53ee6916942c645cd9e28778c238a5"
+dependencies = [
+ "displaydoc",
+ "icu_locale_core",
+ "icu_provider_macros 2.0.0-beta1",
+ "stable_deref_trait",
+ "tinystr 0.8.0",
+ "writeable 0.6.0",
+ "yoke",
+ "zerofrom",
+ "zerovec 0.11.0",
 ]
 
 [[package]]
@@ -1932,10 +2018,21 @@ checksum = "d6324dfd08348a8e0374a447ebd334044d766b1839bb8d5ccf2482a99a77c0bc"
 dependencies = [
  "icu_locid",
  "icu_locid_transform",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
- "tinystr",
- "zerovec",
+ "tinystr 0.7.6",
+ "zerovec 0.10.4",
+]
+
+[[package]]
+name = "icu_provider_baked"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7c6494d25b75593ad56dcd9bde1040ef7e22e9c70b24c1de8920d9a919118893"
+dependencies = [
+ "icu_provider 2.0.0-beta1",
+ "writeable 0.6.0",
+ "zerotrie 0.2.0",
 ]
 
 [[package]]
@@ -1944,13 +2041,13 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c24b98d1365f55d78186c205817631a4acf08d7a45bdf5dc9dcf9c5d54dccf51"
 dependencies = [
- "icu_provider",
+ "icu_provider 1.5.0",
  "log",
  "postcard",
  "serde",
- "writeable",
- "zerotrie",
- "zerovec",
+ "writeable 0.5.5",
+ "zerotrie 0.1.3",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1964,6 +2061,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "icu_provider_macros"
+version = "2.0.0-beta1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba0c1a4c9cca68c00053013b9ad7dc7d2e69aefed59dd9e38cb63347c28299b0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "icu_segmenter"
 version = "1.5.0"
@@ -1973,12 +2081,12 @@ dependencies = [
  "core_maths",
  "databake",
  "displaydoc",
- "icu_collections",
+ "icu_collections 1.5.0",
  "icu_locid",
- "icu_provider",
+ "icu_provider 1.5.0",
  "serde",
  "utf8_iter",
- "zerovec",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -1989,12 +2097,12 @@ checksum = "aa91ba6a585939a020c787235daa8aee856d9bceebd6355e283c0c310bc6de96"
 dependencies = [
  "databake",
  "displaydoc",
- "icu_calendar",
- "icu_provider",
+ "icu_calendar 1.5.2",
+ "icu_provider 1.5.0",
  "serde",
- "tinystr",
- "zerotrie",
- "zerovec",
+ "tinystr 0.7.6",
+ "zerotrie 0.1.3",
+ "zerovec 0.10.4",
 ]
 
 [[package]]
@@ -2134,11 +2242,12 @@ checksum = "d75a2a4b1b190afb6f5425f10f6a8f959d2ea0b9c2b1d79553551850539e4674"
 
 [[package]]
 name = "ixdtf"
-version = "0.2.0"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2123305f927452a9502fc05c33800280d90127c95c50eb45ec6b3c50346afbf3"
+checksum = "fb6cd1080e64f68b07c577e3c687f4a894b3d1bd6093cb36b55c7bd07675aa3a"
 dependencies = [
  "displaydoc",
+ "utf8_iter",
 ]
 
 [[package]]
@@ -2730,6 +2839,16 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "potential_utf"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2a1d6d1132e166768a82805efecd7c326eb8dc70ad4a586da697836b44eb970"
+dependencies = [
+ "serde",
+ "zerovec 0.11.0",
+]
+
 [[package]]
 name = "powerfmt"
 version = "0.2.0"
@@ -3348,17 +3467,17 @@ checksum = "42a4d50cdb458045afc8131fd91b64904da29548bcb63c7236e0844936c13078"
 [[package]]
 name = "temporal_rs"
 version = "0.0.4"
-source = "git+https://github.com/boa-dev/temporal.git?rev=016bc31d2ce5484973b71ccdb0faeb33c00a9ae6#016bc31d2ce5484973b71ccdb0faeb33c00a9ae6"
+source = "git+https://github.com/boa-dev/temporal.git?rev=4498edf4efa52f0cdec0bbed8bf49cae7e543e74#4498edf4efa52f0cdec0bbed8bf49cae7e543e74"
 dependencies = [
  "bitflags 2.6.0",
  "combine",
  "iana-time-zone",
- "icu_calendar",
+ "icu_calendar 2.0.0-beta1",
  "ixdtf",
  "jiff-tzdb",
  "num-traits",
  "rustc-hash 2.1.0",
- "tinystr",
+ "tinystr 0.8.0",
  "tzif",
  "web-time",
 ]
@@ -3501,7 +3620,17 @@ dependencies = [
  "databake",
  "displaydoc",
  "serde",
- "zerovec",
+ "zerovec 0.10.4",
+]
+
+[[package]]
+name = "tinystr"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2b56a820bb70060f096338fcc02edb78cb3f8fb21c5078503f48588cfcaf494"
+dependencies = [
+ "displaydoc",
+ "zerovec 0.11.0",
 ]
 
 [[package]]
@@ -3649,9 +3778,9 @@ dependencies = [
 
 [[package]]
 name = "tzif"
-version = "0.2.3"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61b8eb18929606c6f3eea7ef096a91dd5c26dbbde2a20a343c4a409b851666fd"
+checksum = "5cecffbab91858408738280e7bb6aac788f59a522dda961cd6b15542f0c08559"
 dependencies = [
  "combine",
 ]
@@ -4158,6 +4287,12 @@ dependencies = [
  "either",
 ]
 
+[[package]]
+name = "writeable"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "74b3b5b7c6114bf7253093603034e102d479ecc8501deca33b6c1c816418b6d2"
+
 [[package]]
 name = "yoke"
 version = "0.7.5"
@@ -4242,7 +4377,16 @@ dependencies = [
  "serde",
  "yoke",
  "zerofrom",
- "zerovec",
+ "zerovec 0.10.4",
+]
+
+[[package]]
+name = "zerotrie"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa766b97d68da210d29cc0bc8d072d87de9359cb998e4bc30ab4982a1c795d47"
+dependencies = [
+ "displaydoc",
 ]
 
 [[package]]
@@ -4255,7 +4399,18 @@ dependencies = [
  "serde",
  "yoke",
  "zerofrom",
- "zerovec-derive",
+ "zerovec-derive 0.10.3",
+]
+
+[[package]]
+name = "zerovec"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b622856b789971a6fe0442b69f3a2d7ac949005c4c8586b2c4ef09cc5182f2b"
+dependencies = [
+ "yoke",
+ "zerofrom",
+ "zerovec-derive 0.11.0",
 ]
 
 [[package]]
@@ -4269,6 +4424,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "zerovec-derive"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "996c67268f00e216986ac140d8de9f47968c330b96aeefcae9ed296f23934448"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "zip"
 version = "0.6.6"
diff --git a/Cargo.toml b/Cargo.toml
index fc619a70f4d..0b8b5119508 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -112,7 +112,7 @@ intrusive-collections = "0.9.7"
 cfg-if = "1.0.0"
 either = "1.13.0"
 sys-locale = "0.3.2"
-temporal_rs = { git = "https://github.com/boa-dev/temporal.git", rev = "016bc31d2ce5484973b71ccdb0faeb33c00a9ae6", features = ["tzdb", "now"] }
+temporal_rs = { git = "https://github.com/boa-dev/temporal.git", rev = "4498edf4efa52f0cdec0bbed8bf49cae7e543e74", features = ["tzdb", "now"] }
 web-time = "1.1.0"
 criterion = "0.5.1"
 float-cmp = "0.10.0"
diff --git a/core/engine/src/builtins/temporal/duration/mod.rs b/core/engine/src/builtins/temporal/duration/mod.rs
index f71c28391b3..0fd300cf6e1 100644
--- a/core/engine/src/builtins/temporal/duration/mod.rs
+++ b/core/engine/src/builtins/temporal/duration/mod.rs
@@ -2,7 +2,7 @@
 
 use super::{
     options::{get_temporal_unit, TemporalUnitGroup},
-    to_integer_if_integral, DateTimeValues,
+    DateTimeValues,
 };
 use crate::value::JsVariant;
 use crate::{
@@ -16,14 +16,14 @@ use crate::{
     property::Attribute,
     realm::Realm,
     string::StaticJsStrings,
-    Context, JsArgs, JsData, JsNativeError, JsObject, JsResult, JsString, JsSymbol, JsValue,
+    Context, JsArgs, JsData, JsError, JsNativeError, JsObject, JsResult, JsString, JsSymbol,
+    JsValue,
 };
 use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
 use temporal_rs::{
     options::{RelativeTo, RoundingIncrement, RoundingOptions, TemporalRoundingMode, TemporalUnit},
     partial::PartialDuration,
-    primitive::FiniteF64,
     Duration as InnerDuration,
 };
 
@@ -222,66 +222,96 @@ impl BuiltInConstructor for Duration {
         }
 
         // 2. If years is undefined, let y be 0; else let y be ? ToIntegerIfIntegral(years).
-        let years = args
-            .get_or_undefined(0)
-            .map_or(Ok(0), |y| to_integer_if_integral(y, context))?;
+        let years = args.get_or_undefined(0).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 3. If months is undefined, let mo be 0; else let mo be ? ToIntegerIfIntegral(months).
-        let months = args
-            .get_or_undefined(1)
-            .map_or(Ok(0), |mo| to_integer_if_integral(mo, context))?;
+        let months = args.get_or_undefined(1).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 4. If weeks is undefined, let w be 0; else let w be ? ToIntegerIfIntegral(weeks).
-        let weeks = args
-            .get_or_undefined(2)
-            .map_or(Ok(0), |wk| to_integer_if_integral(wk, context))?;
+        let weeks = args.get_or_undefined(2).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 5. If days is undefined, let d be 0; else let d be ? ToIntegerIfIntegral(days).
-        let days = args
-            .get_or_undefined(3)
-            .map_or(Ok(0), |d| to_integer_if_integral(d, context))?;
+        let days = args.get_or_undefined(3).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 6. If hours is undefined, let h be 0; else let h be ? ToIntegerIfIntegral(hours).
-        let hours = args
-            .get_or_undefined(4)
-            .map_or(Ok(0), |h| to_integer_if_integral(h, context))?;
+        let hours = args.get_or_undefined(4).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 7. If minutes is undefined, let m be 0; else let m be ? ToIntegerIfIntegral(minutes).
-        let minutes = args
-            .get_or_undefined(5)
-            .map_or(Ok(0), |m| to_integer_if_integral(m, context))?;
+        let minutes = args.get_or_undefined(5).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 8. If seconds is undefined, let s be 0; else let s be ? ToIntegerIfIntegral(seconds).
-        let seconds = args
-            .get_or_undefined(6)
-            .map_or(Ok(0), |s| to_integer_if_integral(s, context))?;
+        let seconds = args.get_or_undefined(6).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 9. If milliseconds is undefined, let ms be 0; else let ms be ? ToIntegerIfIntegral(milliseconds).
-        let milliseconds = args
-            .get_or_undefined(7)
-            .map_or(Ok(0), |ms| to_integer_if_integral(ms, context))?;
+        let milliseconds = args.get_or_undefined(7).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 10. If microseconds is undefined, let mis be 0; else let mis be ? ToIntegerIfIntegral(microseconds).
-        let microseconds = args
-            .get_or_undefined(8)
-            .map_or(Ok(0), |mis| to_integer_if_integral(mis, context))?;
+        let microseconds = args.get_or_undefined(8).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         // 11. If nanoseconds is undefined, let ns be 0; else let ns be ? ToIntegerIfIntegral(nanoseconds).
-        let nanoseconds = args
-            .get_or_undefined(9)
-            .map_or(Ok(0), |ns| to_integer_if_integral(ns, context))?;
+        let nanoseconds = args.get_or_undefined(9).map_or(Ok(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)
+        })?;
 
         let record = InnerDuration::new(
-            years.into(),
-            months.into(),
-            weeks.into(),
-            days.into(),
-            hours.into(),
-            minutes.into(),
-            seconds.into(),
-            milliseconds.into(),
-            microseconds.into(),
-            nanoseconds.into(),
+            years.try_into()?,
+            months.try_into()?,
+            weeks.try_into()?,
+            days.try_into()?,
+            hours.try_into()?,
+            minutes.try_into()?,
+            seconds.try_into()?,
+            milliseconds.try_into()?,
+            microseconds.try_into()?,
+            nanoseconds.try_into()?,
         )?;
 
         // 12. Return ? CreateTemporalDuration(y, mo, w, d, h, m, s, ms, mis, ns, NewTarget).
@@ -929,119 +959,160 @@ pub(crate) fn to_temporal_partial_duration(
     };
 
     // 2. Let result be a new partial Duration Record with each field set to undefined.
-    let mut result = PartialDuration::default();
-
     // 3. NOTE: The following steps read properties and perform independent validation in alphabetical order.
     // 4. Let days be ? Get(temporalDurationLike, "days").
-    let days = unknown_object.get(js_string!("days"), context)?;
-    if !days.is_undefined() {
-        // 5. If days is not undefined, set result.[[Days]] to ? ToIntegerIfIntegral(days).
-        let _ = result
-            .days
-            .insert(FiniteF64::from(to_integer_if_integral(&days, context)?));
-    }
+    // 5. If days is not undefined, set result.[[Days]] to ? ToIntegerIfIntegral(days).
+    let days = unknown_object
+        .get(js_string!("days"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 6. Let hours be ? Get(temporalDurationLike, "hours").
-    let hours = unknown_object.get(js_string!("hours"), context)?;
     // 7. If hours is not undefined, set result.[[Hours]] to ? ToIntegerIfIntegral(hours).
-    if !hours.is_undefined() {
-        let _ = result
-            .hours
-            .insert(FiniteF64::from(to_integer_if_integral(&hours, context)?));
-    }
+    let hours = unknown_object
+        .get(js_string!("hours"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 8. Let microseconds be ? Get(temporalDurationLike, "microseconds").
-    let microseconds = unknown_object.get(js_string!("microseconds"), context)?;
     // 9. If microseconds is not undefined, set result.[[Microseconds]] to ? ToIntegerIfIntegral(microseconds).
-    if !microseconds.is_undefined() {
-        let _ = result
-            .microseconds
-            .insert(FiniteF64::from(to_integer_if_integral(
-                &microseconds,
-                context,
-            )?));
-    }
+    let microseconds = unknown_object
+        .get(js_string!("microseconds"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 10. Let milliseconds be ? Get(temporalDurationLike, "milliseconds").
-    let milliseconds = unknown_object.get(js_string!("milliseconds"), context)?;
     // 11. If milliseconds is not undefined, set result.[[Milliseconds]] to ? ToIntegerIfIntegral(milliseconds).
-    if !milliseconds.is_undefined() {
-        let _ = result
-            .milliseconds
-            .insert(FiniteF64::from(to_integer_if_integral(
-                &milliseconds,
-                context,
-            )?));
-    }
+    let milliseconds = unknown_object
+        .get(js_string!("milliseconds"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 12. Let minutes be ? Get(temporalDurationLike, "minutes").
-    let minutes = unknown_object.get(js_string!("minutes"), context)?;
     // 13. If minutes is not undefined, set result.[[Minutes]] to ? ToIntegerIfIntegral(minutes).
-    if !minutes.is_undefined() {
-        let _ = result
-            .minutes
-            .insert(FiniteF64::from(to_integer_if_integral(&minutes, context)?));
-    }
+    let minutes = unknown_object
+        .get(js_string!("minutes"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 14. Let months be ? Get(temporalDurationLike, "months").
-    let months = unknown_object.get(js_string!("months"), context)?;
     // 15. If months is not undefined, set result.[[Months]] to ? ToIntegerIfIntegral(months).
-    if !months.is_undefined() {
-        let _ = result
-            .months
-            .insert(FiniteF64::from(to_integer_if_integral(&months, context)?));
-    }
+    let months = unknown_object
+        .get(js_string!("months"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 16. Let nanoseconds be ? Get(temporalDurationLike, "nanoseconds").
-    let nanoseconds = unknown_object.get(js_string!("nanoseconds"), context)?;
     // 17. If nanoseconds is not undefined, set result.[[Nanoseconds]] to ? ToIntegerIfIntegral(nanoseconds).
-    if !nanoseconds.is_undefined() {
-        let _ = result
-            .nanoseconds
-            .insert(FiniteF64::from(to_integer_if_integral(
-                &nanoseconds,
-                context,
-            )?));
-    }
+    let nanoseconds = unknown_object
+        .get(js_string!("nanoseconds"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 18. Let seconds be ? Get(temporalDurationLike, "seconds").
-    let seconds = unknown_object.get(js_string!("seconds"), context)?;
     // 19. If seconds is not undefined, set result.[[Seconds]] to ? ToIntegerIfIntegral(seconds).
-    if !seconds.is_undefined() {
-        let _ = result
-            .seconds
-            .insert(FiniteF64::from(to_integer_if_integral(&seconds, context)?));
-    }
+    let seconds = unknown_object
+        .get(js_string!("seconds"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 20. Let weeks be ? Get(temporalDurationLike, "weeks").
-    let weeks = unknown_object.get(js_string!("weeks"), context)?;
     // 21. If weeks is not undefined, set result.[[Weeks]] to ? ToIntegerIfIntegral(weeks).
-    if !weeks.is_undefined() {
-        let _ = result
-            .weeks
-            .insert(FiniteF64::from(to_integer_if_integral(&weeks, context)?));
-    }
+    let weeks = unknown_object
+        .get(js_string!("weeks"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
 
     // 22. Let years be ? Get(temporalDurationLike, "years").
-    let years = unknown_object.get(js_string!("years"), context)?;
     // 23. If years is not undefined, set result.[[Years]] to ? ToIntegerIfIntegral(years).
-    if !years.is_undefined() {
-        let _ = result
-            .years
-            .insert(FiniteF64::from(to_integer_if_integral(&years, context)?));
-    }
+    let years = unknown_object
+        .get(js_string!("years"), context)?
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            let integral_int = finite
+                .as_integer_if_integral::<i64>()
+                .map_err(JsError::from)?;
+            integral_int.try_into().map_err(JsError::from)
+        })
+        .transpose()?;
+
+    let partial = PartialDuration {
+        years,
+        months,
+        weeks,
+        days,
+        hours,
+        minutes,
+        seconds,
+        milliseconds,
+        microseconds,
+        nanoseconds,
+    };
 
-    // TODO: Implement this functionality better in `temporal_rs`.
     // 24. If years is undefined, and months is undefined, and weeks is undefined, and days
     // is undefined, and hours is undefined, and minutes is undefined, and seconds is
     // undefined, and milliseconds is undefined, and microseconds is undefined, and
     // nanoseconds is undefined, throw a TypeError exception.
-    if result.is_empty() {
+    if partial.is_empty() {
         return Err(JsNativeError::typ()
             .with_message("PartialDurationRecord must have a defined field.")
             .into());
     }
 
     // 25. Return result.
-    Ok(result)
+    Ok(partial)
 }
diff --git a/core/engine/src/builtins/temporal/instant/mod.rs b/core/engine/src/builtins/temporal/instant/mod.rs
index 182491fbc79..5fe1f9d16d3 100644
--- a/core/engine/src/builtins/temporal/instant/mod.rs
+++ b/core/engine/src/builtins/temporal/instant/mod.rs
@@ -31,7 +31,7 @@ use temporal_rs::{
 };
 
 /// The `Temporal.Instant` object.
-#[derive(Debug, Clone, Trace, Finalize, JsData)]
+#[derive(Debug, Clone, Copy, Trace, Finalize, JsData)]
 // SAFETY: Instant does not contain any traceable values.
 #[boa_gc(unsafe_empty_trace)]
 pub struct Instant {
@@ -530,7 +530,7 @@ fn to_temporal_instant(item: &JsValue, context: &mut Context) -> JsResult<InnerI
         // c. NOTE: This use of ToPrimitive allows Instant-like objects to be converted.
         // d. Set item to ? ToPrimitive(item, string).
         if let Some(instant) = obj.downcast_ref::<Instant>() {
-            return Ok(instant.inner.clone());
+            return Ok(instant.inner);
         } else if let Some(_zdt) = obj.downcast_ref::<ZonedDateTime>() {
             return Err(JsNativeError::error()
                 .with_message("Not yet implemented.")
diff --git a/core/engine/src/builtins/temporal/mod.rs b/core/engine/src/builtins/temporal/mod.rs
index 0769ef4af23..bb814a0a6e1 100644
--- a/core/engine/src/builtins/temporal/mod.rs
+++ b/core/engine/src/builtins/temporal/mod.rs
@@ -1,5 +1,8 @@
 //! The ECMAScript `Temporal` stage 3 built-in implementation.
 //!
+//! Boa's Temporal implementation uses the `temporal_rs` crate
+//! for the core functionality of the implementation.
+//!
 //! More information:
 //!
 //! [spec]: https://tc39.es/proposal-temporal/
@@ -38,7 +41,10 @@ use crate::{
     Context, JsBigInt, JsNativeError, JsObject, JsResult, JsString, JsSymbol, JsValue,
 };
 use boa_profiler::Profiler;
-use temporal_rs::{PlainDate as TemporalDate, ZonedDateTime as TemporalZonedDateTime, NS_PER_DAY};
+use temporal_rs::{
+    primitive::FiniteF64, PlainDate as TemporalDate, ZonedDateTime as TemporalZonedDateTime,
+    NS_PER_DAY,
+};
 
 // TODO: Remove in favor of `temporal_rs`
 pub(crate) fn ns_max_instant() -> JsBigInt {
@@ -209,33 +215,6 @@ pub(crate) fn _iterator_to_list_of_types(
     Ok(values)
 }
 
-// Abstract Operation 13.3 `EpochDaysToEpochMs`
-// Migrated to `temporal_rs`
-
-// 13.4 Date Equations
-// implemented in temporal/date_equations.rs
-
-// Abstract Operation 13.5 `GetOptionsObject ( options )`
-// Implemented in builtin/options.rs
-
-// 13.6 `GetOption ( options, property, type, values, default )`
-// Implemented in builtin/options.rs
-
-// 13.7 `ToTemporalOverflow (options)`
-// Now implemented in temporal/options.rs
-
-// 13.10 `ToTemporalRoundingMode ( normalizedOptions, fallback )`
-// Now implemented in builtin/options.rs
-
-// 13.11 `NegateTemporalRoundingMode ( roundingMode )`
-// Now implemented in builtin/options.rs
-
-// 13.16 `ToTemporalRoundingIncrement ( normalizedOptions )`
-// Now implemented in temporal/options.rs
-
-// 13.17 `ValidateTemporalRoundingIncrement ( increment, dividend, inclusive )`
-// Moved to temporal_rs
-
 type RelativeTemporalObjectResult = JsResult<(Option<TemporalDate>, Option<TemporalZonedDateTime>)>;
 
 /// 13.21 `ToRelativeTemporalObject ( options )`
@@ -260,15 +239,6 @@ pub(crate) fn to_relative_temporal_object(
     Ok((Some(plain_date), None))
 }
 
-// 13.22 `LargerOfTwoTemporalUnits ( u1, u2 )`
-// use core::cmp::max
-
-// 13.23 `MaximumTemporalDurationRoundingIncrement ( unit )`
-// Implemented on TemporalUnit in temporal/options.rs
-
-// 13.26 `GetUnsignedRoundingMode ( roundingMode, isNegative )`
-// Implemented on RoundingMode in builtins/options.rs
-
 // 13.26 IsPartialTemporalObject ( object )
 pub(crate) fn is_partial_temporal_object<'value>(
     value: &'value JsValue,
@@ -309,79 +279,14 @@ pub(crate) fn is_partial_temporal_object<'value>(
     Ok(Some(obj))
 }
 
-// 13.27 `ApplyUnsignedRoundingMode ( x, r1, r2, unsignedRoundingMode )`
-// Migrated to `temporal_rs`
-
-// 13.28 `RoundNumberToIncrement ( x, increment, roundingMode )`
-// Migrated to `temporal_rs`
-
-// 13.29 `RoundNumberToIncrementAsIfPositive ( x, increment, roundingMode )`
-// Migrated to `temporal_rs`
-
-/// 13.43 `ToPositiveIntegerWithTruncation ( argument )`
-#[inline]
-#[allow(unused)]
-pub(crate) fn to_positive_integer_with_trunc(
-    value: &JsValue,
-    context: &mut Context,
-) -> JsResult<i32> {
-    // 1. Let integer be ? ToIntegerWithTruncation(argument).
-    let int = to_integer_with_truncation(value, context)?;
-    // 2. If integer ≤ 0, throw a RangeError exception.
-    if int <= 0 {
-        return Err(JsNativeError::range()
-            .with_message("value is not a positive integer")
-            .into());
-    }
-    // 3. Return integer.
-    Ok(int)
-}
-
-/// 13.44 `ToIntegerWithTruncation ( argument )`
-#[inline]
-pub(crate) fn to_integer_with_truncation(value: &JsValue, context: &mut Context) -> JsResult<i32> {
-    // 1. Let number be ? ToNumber(argument).
-    let number = value.to_number(context)?;
-    // 2. If number is NaN, +∞𝔽 or -∞𝔽, throw a RangeError exception.
-    if number.is_nan() || number.is_infinite() {
-        return Err(JsNativeError::range()
-            .with_message("truncation target must be an integer.")
-            .into());
+impl JsValue {
+    pub(crate) fn to_finitef64(&self, context: &mut Context) -> JsResult<FiniteF64> {
+        let number = self.to_number(context)?;
+        let result = FiniteF64::try_from(number)?;
+        Ok(result)
     }
-    // 3. Return truncate(ℝ(number)).
-    Ok(number.trunc() as i32)
 }
 
-/// Abstract operation 13.45 `ToIntegerIfIntegral( argument )`
-#[inline]
-pub(crate) fn to_integer_if_integral(arg: &JsValue, _context: &mut Context) -> JsResult<i32> {
-    // 1. Let number be ? ToNumber(argument).
-    // 2. If IsIntegralNumber(number) is false, throw a RangeError exception.
-    // 3. Return ℝ(number).
-    let Some(arg) = arg.as_i32() else {
-        return Err(JsNativeError::range()
-            .with_message("value to convert is not an integral number.")
-            .into());
-    };
-
-    Ok(arg)
-}
-
-// 13.46 `PrepareTemporalFields ( fields, fieldNames, requiredFields [ , duplicateBehaviour ] )`
-// See fields.rs
-
-// NOTE: op -> true == until | false == since
-// 13.47 `GetDifferenceSettings ( operation, options, unitGroup, disallowedUnits, fallbackSmallestUnit, smallestLargestDefaultUnit )`
-// Migrated to `temporal_rs`
-
-// NOTE: used for MergeFields methods. Potentially can be omitted in favor of `TemporalFields`.
-// 14.6 `CopyDataProperties ( target, source, excludedKeys [ , excludedValues ] )`
-// Migrated or repurposed to `temporal_rs`/`fields.rs`
-
-// Note: Deviates from Proposal spec -> proto appears to be always null across the specification.
-// 14.7 `SnapshotOwnProperties ( source, proto [ , excludedKeys [ , excludedValues ] ] )`
-// Migrated or repurposed to `temporal_rs`/`fields.rs`
-
 fn extract_from_temporal_type<DF, DTF, YMF, MDF, ZDTF, Ret>(
     object: &JsObject,
     date_f: DF,
diff --git a/core/engine/src/builtins/temporal/plain_date/mod.rs b/core/engine/src/builtins/temporal/plain_date/mod.rs
index f58411ecab1..8b914b4e85f 100644
--- a/core/engine/src/builtins/temporal/plain_date/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_date/mod.rs
@@ -21,8 +21,7 @@ use crate::{
 use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
 use temporal_rs::{
-    options::ArithmeticOverflow, partial::PartialDate, Calendar, PlainDate as InnerDate,
-    TinyAsciiStr,
+    options::ArithmeticOverflow, partial::PartialDate, PlainDate as InnerDate, TinyAsciiStr,
 };
 
 use super::{
@@ -244,20 +243,23 @@ impl BuiltInConstructor for PlainDate {
                 .into());
         };
 
-        let iso_year = super::to_integer_with_truncation(args.get_or_undefined(0), context)?;
-        let iso_month = super::to_integer_with_truncation(args.get_or_undefined(1), context)?;
-        let iso_day = super::to_integer_with_truncation(args.get_or_undefined(2), context)?;
+        let year = args
+            .get_or_undefined(0)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<i32>();
+        let month = args
+            .get_or_undefined(1)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<u8>();
+        let day = args
+            .get_or_undefined(2)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<u8>();
         let calendar_slot = to_temporal_calendar_slot_value(args.get_or_undefined(3))?;
 
-        Ok(create_temporal_date(
-            iso_year,
-            iso_month,
-            iso_day,
-            calendar_slot,
-            Some(new_target),
-            context,
-        )?
-        .into())
+        let inner = InnerDate::try_new(year, month.into(), day.into(), calendar_slot)?;
+
+        Ok(create_temporal_date(inner, Some(new_target), context)?.into())
     }
 }
 
@@ -491,27 +493,11 @@ impl PlainDate {
         if let Some(date) = item.as_object().and_then(JsObject::downcast_ref::<Self>) {
             let options = get_options_object(options.unwrap_or(&JsValue::undefined()))?;
             let _ = get_option::<ArithmeticOverflow>(&options, js_string!("overflow"), context)?;
-            return create_temporal_date(
-                date.inner.iso_year(),
-                date.inner.iso_month().into(),
-                date.inner.iso_day().into(),
-                date.inner.calendar().clone(),
-                None,
-                context,
-            )
-            .map(Into::into);
+            return create_temporal_date(date.inner.clone(), None, context).map(Into::into);
         }
 
         let resolved_date = to_temporal_date(item, options.cloned(), context)?;
-        create_temporal_date(
-            resolved_date.iso_year(),
-            resolved_date.iso_month().into(),
-            resolved_date.iso_day().into(),
-            resolved_date.calendar().clone(),
-            None,
-            context,
-        )
-        .map(Into::into)
+        create_temporal_date(resolved_date, None, context).map(Into::into)
     }
 
     /// 3.2.3 Temporal.PlainDate.compare ( one, two )
@@ -600,15 +586,7 @@ impl PlainDate {
         // 5. Let calendarRec be ? CreateCalendarMethodsRecord(temporalDate.[[Calendar]], « date-add »).
         // 6. Return ? AddDate(calendarRec, temporalDate, duration, options).
         let resolved_date = date.inner.add(&duration, overflow)?;
-        create_temporal_date(
-            resolved_date.iso_year(),
-            resolved_date.iso_month().into(),
-            resolved_date.iso_day().into(),
-            resolved_date.calendar().clone(),
-            None,
-            context,
-        )
-        .map(Into::into)
+        create_temporal_date(resolved_date, None, context).map(Into::into)
     }
 
     fn subtract(this: &JsValue, args: &[JsValue], context: &mut Context) -> JsResult<JsValue> {
@@ -632,15 +610,7 @@ impl PlainDate {
         // 6. Let calendarRec be ? CreateCalendarMethodsRecord(temporalDate.[[Calendar]], « date-add »).
         // 7. Return ? AddDate(calendarRec, temporalDate, negatedDuration, options).
         let resolved_date = date.inner.subtract(&duration, overflow)?;
-        create_temporal_date(
-            resolved_date.iso_year(),
-            resolved_date.iso_month().into(),
-            resolved_date.iso_day().into(),
-            resolved_date.calendar().clone(),
-            None,
-            context,
-        )
-        .map(Into::into)
+        create_temporal_date(resolved_date, None, context).map(Into::into)
     }
 
     // 3.3.24 Temporal.PlainDate.prototype.with ( temporalDateLike [ , options ] )
@@ -677,15 +647,7 @@ impl PlainDate {
 
         // 10. Return ? CalendarDateFromFields(calendarRec, fields, resolvedOptions).
         let resolved_date = date.inner.with(partial, overflow)?;
-        create_temporal_date(
-            resolved_date.iso_year(),
-            resolved_date.iso_month().into(),
-            resolved_date.iso_day().into(),
-            resolved_date.calendar().clone(),
-            None,
-            context,
-        )
-        .map(Into::into)
+        create_temporal_date(resolved_date, None, context).map(Into::into)
     }
 
     /// 3.3.26 Temporal.PlainDate.prototype.withCalendar ( calendarLike )
@@ -699,15 +661,7 @@ impl PlainDate {
 
         let calendar = to_temporal_calendar_slot_value(args.get_or_undefined(0))?;
         let resolved_date = date.inner.with_calendar(calendar)?;
-        create_temporal_date(
-            resolved_date.iso_year(),
-            resolved_date.iso_month().into(),
-            resolved_date.iso_day().into(),
-            resolved_date.calendar().clone(),
-            None,
-            context,
-        )
-        .map(Into::into)
+        create_temporal_date(resolved_date, None, context).map(Into::into)
     }
 
     fn until(this: &JsValue, args: &[JsValue], context: &mut Context) -> JsResult<JsValue> {
@@ -797,14 +751,7 @@ impl PlainDate {
 impl PlainDate {
     /// Utitily function for translating a `Temporal.PlainDate` into a `JsObject`.
     pub(crate) fn as_object(&self, context: &mut Context) -> JsResult<JsObject> {
-        create_temporal_date(
-            self.inner.iso_year(),
-            self.inner.iso_month().into(),
-            self.inner.iso_day().into(),
-            self.inner.calendar().clone(),
-            None,
-            context,
-        )
+        create_temporal_date(self.inner.clone(), None, context)
     }
 }
 
@@ -813,16 +760,12 @@ impl PlainDate {
 
 /// 3.5.3 `CreateTemporalDate ( isoYear, isoMonth, isoDay, calendar [ , newTarget ] )`
 pub(crate) fn create_temporal_date(
-    iso_year: i32,
-    iso_month: i32,
-    iso_day: i32,
-    calendar_slot: Calendar,
+    inner: InnerDate,
     new_target: Option<&JsValue>,
     context: &mut Context,
 ) -> JsResult<JsObject> {
     // 1. If IsValidISODate(isoYear, isoMonth, isoDay) is false, throw a RangeError exception.
     // 2. If ISODateTimeWithinLimits(isoYear, isoMonth, isoDay, 12, 0, 0, 0, 0, 0) is false, throw a RangeError exception.
-    let inner = InnerDate::try_new(iso_year, iso_month, iso_day, calendar_slot)?;
 
     // 3. If newTarget is not present, set newTarget to %Temporal.PlainDate%.
     let new_target = if let Some(new_target) = new_target {
@@ -958,11 +901,21 @@ pub(crate) fn to_partial_date_record(
     // TODO: Most likely need to use an iterator to handle.
     let day = partial_object
         .get(js_string!("day"), context)?
-        .map(|v| super::to_positive_integer_with_trunc(v, context))
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_positive_integer_with_truncation()
+                .map_err(JsError::from)
+        })
         .transpose()?;
     let month = partial_object
         .get(js_string!("month"), context)?
-        .map(|v| super::to_positive_integer_with_trunc(v, context))
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            finite
+                .as_positive_integer_with_truncation()
+                .map_err(JsError::from)
+        })
         .transpose()?;
     let month_code = partial_object
         .get(js_string!("monthCode"), context)?
@@ -973,17 +926,23 @@ pub(crate) fn to_partial_date_record(
                     .with_message("The monthCode field value must be a string.")
                     .into());
             };
-            TinyAsciiStr::<4>::from_str(&month_code.to_std_string_escaped())
+            TinyAsciiStr::<4>::try_from_str(&month_code.to_std_string_escaped())
                 .map_err(|e| JsError::from(JsNativeError::typ().with_message(e.to_string())))
         })
         .transpose()?;
     let year = partial_object
         .get(js_string!("year"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<i32, JsError>(finite.as_integer_with_truncation::<i32>())
+        })
         .transpose()?;
     let era_year = partial_object
         .get(js_string!("eraYear"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<i32, JsError>(finite.as_integer_with_truncation::<i32>())
+        })
         .transpose()?;
     let era = partial_object
         .get(js_string!("era"), context)?
@@ -996,7 +955,7 @@ pub(crate) fn to_partial_date_record(
                 ));
             };
             // TODO: double check if an invalid monthCode is a range or type error.
-            TinyAsciiStr::<19>::from_str(&era.to_std_string_escaped())
+            TinyAsciiStr::<19>::try_from_str(&era.to_std_string_escaped())
                 .map_err(|e| JsError::from(JsNativeError::range().with_message(e.to_string())))
         })
         .transpose()?;
diff --git a/core/engine/src/builtins/temporal/plain_date_time/mod.rs b/core/engine/src/builtins/temporal/plain_date_time/mod.rs
index 73811ecc439..d7ab63c04dc 100644
--- a/core/engine/src/builtins/temporal/plain_date_time/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_date_time/mod.rs
@@ -4,7 +4,7 @@
 use crate::{
     builtins::{
         options::{get_option, get_options_object},
-        temporal::{to_integer_with_truncation, to_partial_date_record, to_partial_time_record},
+        temporal::{to_partial_date_record, to_partial_time_record},
         BuiltInBuilder, BuiltInConstructor, BuiltInObject, IntrinsicObject,
     },
     context::intrinsics::{Intrinsics, StandardConstructor, StandardConstructors},
@@ -14,7 +14,8 @@ use crate::{
     realm::Realm,
     string::StaticJsStrings,
     value::IntoOrUndefined,
-    Context, JsArgs, JsData, JsNativeError, JsObject, JsResult, JsString, JsSymbol, JsValue,
+    Context, JsArgs, JsData, JsError, JsNativeError, JsObject, JsResult, JsString, JsSymbol,
+    JsValue,
 };
 use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
@@ -22,6 +23,12 @@ use boa_profiler::Profiler;
 #[cfg(test)]
 mod tests;
 
+use temporal_rs::{
+    options::{ArithmeticOverflow, RoundingIncrement, RoundingOptions, TemporalRoundingMode},
+    partial::PartialDateTime,
+    PlainDateTime as InnerDateTime, PlainTime,
+};
+
 use super::{
     calendar::{get_temporal_calendar_slot_value_with_default, to_temporal_calendar_slot_value},
     create_temporal_duration,
@@ -29,11 +36,6 @@ use super::{
     to_temporal_duration_record, to_temporal_time, PlainDate, ZonedDateTime,
 };
 use crate::value::JsVariant;
-use temporal_rs::{
-    options::{ArithmeticOverflow, RoundingIncrement, RoundingOptions, TemporalRoundingMode},
-    partial::PartialDateTime,
-    PlainDateTime as InnerDateTime, PlainTime,
-};
 
 /// The `Temporal.PlainDateTime` object.
 #[derive(Debug, Clone, Trace, Finalize, JsData)]
@@ -308,48 +310,73 @@ impl BuiltInConstructor for PlainDateTime {
         };
 
         // 2. Set isoYear to ? ToIntegerWithTruncation(isoYear).
-        let iso_year = to_integer_with_truncation(args.get_or_undefined(0), context)?;
+        let iso_year = args
+            .get_or_undefined(0)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<i32>();
         // 3. Set isoMonth to ? ToIntegerWithTruncation(isoMonth).
-        let iso_month = to_integer_with_truncation(args.get_or_undefined(1), context)?;
+        let iso_month = args
+            .get_or_undefined(1)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<u8>();
         // 4. Set isoDay to ? ToIntegerWithTruncation(isoDay).
-        let iso_day = to_integer_with_truncation(args.get_or_undefined(2), context)?;
+        let iso_day = args
+            .get_or_undefined(2)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<u8>();
         // 5. If hour is undefined, set hour to 0; else set hour to ? ToIntegerWithTruncation(hour).
-        let hour = args
-            .get_or_undefined(3)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+        let hour = args.get_or_undefined(3).map_or(Ok::<u8, JsError>(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            Ok(finite.as_integer_with_truncation::<u8>())
+        })?;
         // 6. If minute is undefined, set minute to 0; else set minute to ? ToIntegerWithTruncation(minute).
-        let minute = args
-            .get_or_undefined(4)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+        let minute = args.get_or_undefined(4).map_or(Ok::<u8, JsError>(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            Ok(finite.as_integer_with_truncation::<u8>())
+        })?;
+
         // 7. If second is undefined, set second to 0; else set second to ? ToIntegerWithTruncation(second).
-        let second = args
-            .get_or_undefined(5)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+        let second = args.get_or_undefined(5).map_or(Ok::<u8, JsError>(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            Ok(finite.as_integer_with_truncation::<u8>())
+        })?;
+
         // 8. If millisecond is undefined, set millisecond to 0; else set millisecond to ? ToIntegerWithTruncation(millisecond).
         let millisecond = args
             .get_or_undefined(6)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+            .map_or(Ok::<u16, JsError>(0), |v| {
+                let finite = v.to_finitef64(context)?;
+                Ok(finite.as_integer_with_truncation::<u16>())
+            })?;
+
         // 9. If microsecond is undefined, set microsecond to 0; else set microsecond to ? ToIntegerWithTruncation(microsecond).
         let microsecond = args
             .get_or_undefined(7)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+            .map_or(Ok::<u16, JsError>(0), |v| {
+                let finite = v.to_finitef64(context)?;
+                Ok(finite.as_integer_with_truncation::<u16>())
+            })?;
+
         // 10. If nanosecond is undefined, set nanosecond to 0; else set nanosecond to ? ToIntegerWithTruncation(nanosecond).
         let nanosecond = args
             .get_or_undefined(8)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
-        // 11. Let calendar be ? ToTemporalCalendarSlotValue(calendarLike, "iso8601").
+            .map_or(Ok::<u16, JsError>(0), |v| {
+                let finite = v.to_finitef64(context)?;
+                Ok(finite.as_integer_with_truncation::<u16>())
+            })?;
+
         let calendar_slot = to_temporal_calendar_slot_value(args.get_or_undefined(9))?;
 
         let dt = InnerDateTime::new(
             iso_year,
-            iso_month,
-            iso_day,
-            hour,
-            minute,
-            second,
-            millisecond,
-            microsecond,
-            nanosecond,
+            iso_month.into(),
+            iso_day.into(),
+            hour.into(),
+            minute.into(),
+            second.into(),
+            millisecond.into(),
+            microsecond.into(),
+            nanosecond.into(),
             calendar_slot,
         )?;
 
diff --git a/core/engine/src/builtins/temporal/plain_month_day/mod.rs b/core/engine/src/builtins/temporal/plain_month_day/mod.rs
index 1713cc005fc..c665d775126 100644
--- a/core/engine/src/builtins/temporal/plain_month_day/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_month_day/mod.rs
@@ -25,10 +25,7 @@ use temporal_rs::{
     PlainDateTime, PlainMonthDay as InnerMonthDay, TinyAsciiStr,
 };
 
-use super::{
-    calendar::to_temporal_calendar_slot_value, to_integer_if_integral,
-    to_positive_integer_with_trunc, DateTimeValues,
-};
+use super::{calendar::to_temporal_calendar_slot_value, DateTimeValues};
 
 /// The `Temporal.PlainMonthDay` object.
 #[derive(Debug, Clone, Trace, Finalize, JsData)]
@@ -201,20 +198,29 @@ impl BuiltInConstructor for PlainMonthDay {
                 .into());
         }
 
-        let year = args.get_or_undefined(3);
-        let ref_year = if year.is_undefined() {
-            None
-        } else {
-            Some(super::to_integer_with_truncation(year, context)?)
-        };
+        let ref_year = args
+            .get_or_undefined(3)
+            .map(|v| {
+                let finite = v.to_finitef64(context)?;
+                Ok::<i32, JsError>(finite.as_integer_with_truncation::<i32>())
+            })
+            .transpose()?;
 
         // We can ignore 2 as the underlying temporal library handles the reference year
-        let m = super::to_integer_with_truncation(args.get_or_undefined(0), context)?;
-        let d = super::to_integer_with_truncation(args.get_or_undefined(1), context)?;
+        let m = args
+            .get_or_undefined(0)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<u8>();
+
+        let d = args
+            .get_or_undefined(1)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<u8>();
+
         let calendar = to_temporal_calendar_slot_value(args.get_or_undefined(2))?;
         let inner = InnerMonthDay::new_with_overflow(
-            m,
-            d,
+            m.into(),
+            d.into(),
             calendar,
             ArithmeticOverflow::Constrain,
             ref_year,
@@ -326,12 +332,24 @@ fn to_temporal_month_day(
     } else if item.is_object() {
         let day = item
             .get_v(js_string!("day"), context)?
-            .map(|v| to_positive_integer_with_trunc(v, context))
+            .map(|v| {
+                let finite = v.to_finitef64(context)?;
+                // TODO: Update to the below to u8 after temporal_rs change
+                finite
+                    .as_positive_integer_with_truncation::<i32>()
+                    .map_err(JsError::from)
+            })
             .transpose()?;
 
         let month = item
             .get_v(js_string!("month"), context)?
-            .map(|v| to_positive_integer_with_trunc(v, context))
+            .map(|v| {
+                let finite = v.to_finitef64(context)?;
+                // TODO: Update to the below to u8 after temporal_rs change
+                finite
+                    .as_positive_integer_with_truncation::<i32>()
+                    .map_err(JsError::from)
+            })
             .transpose()?;
 
         let month_code = item
@@ -348,11 +366,12 @@ fn to_temporal_month_day(
             })
             .transpose()?;
 
-        let year = item
-            .get_v(js_string!("year"), context)?
-            .map(|v| to_integer_if_integral(v, context))
-            .transpose()?
-            .unwrap_or(1972);
+        let year =
+            item.get_v(js_string!("year"), context)?
+                .map_or(Ok::<i32, JsError>(1972), |v| {
+                    let finite = v.to_finitef64(context)?;
+                    Ok(finite.as_integer_with_truncation::<i32>())
+                })?;
 
         let partial_date = &PartialDate {
             month,
diff --git a/core/engine/src/builtins/temporal/plain_time/mod.rs b/core/engine/src/builtins/temporal/plain_time/mod.rs
index fd9679b91ec..e6b015f0b15 100644
--- a/core/engine/src/builtins/temporal/plain_time/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_time/mod.rs
@@ -3,7 +3,7 @@
 use super::{
     create_temporal_duration,
     options::{get_difference_settings, get_temporal_unit, TemporalUnitGroup},
-    to_integer_with_truncation, to_temporal_duration_record, PlainDateTime, ZonedDateTime,
+    to_temporal_duration_record, PlainDateTime, ZonedDateTime,
 };
 use crate::value::JsVariant;
 use crate::{
@@ -17,7 +17,8 @@ use crate::{
     property::Attribute,
     realm::Realm,
     string::StaticJsStrings,
-    Context, JsArgs, JsData, JsNativeError, JsObject, JsResult, JsString, JsSymbol, JsValue,
+    Context, JsArgs, JsData, JsError, JsNativeError, JsObject, JsResult, JsString, JsSymbol,
+    JsValue,
 };
 use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
@@ -149,32 +150,53 @@ impl BuiltInConstructor for PlainTime {
         }
 
         // 2. If hour is undefined, set hour to 0; else set hour to ? ToIntegerWithTruncation(hour).
-        let hour = args
-            .get_or_undefined(0)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+        let hour = args.get_or_undefined(0).map_or(Ok::<u8, JsError>(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            Ok(finite.as_integer_with_truncation::<u8>())
+        })?;
         // 3. If minute is undefined, set minute to 0; else set minute to ? ToIntegerWithTruncation(minute).
-        let minute = args
-            .get_or_undefined(1)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+        let minute = args.get_or_undefined(1).map_or(Ok::<u8, JsError>(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            Ok(finite.as_integer_with_truncation::<u8>())
+        })?;
         // 4. If second is undefined, set second to 0; else set second to ? ToIntegerWithTruncation(second).
-        let second = args
-            .get_or_undefined(2)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+        let second = args.get_or_undefined(2).map_or(Ok::<u8, JsError>(0), |v| {
+            let finite = v.to_finitef64(context)?;
+            Ok(finite.as_integer_with_truncation::<u8>())
+        })?;
+
         // 5. If millisecond is undefined, set millisecond to 0; else set millisecond to ? ToIntegerWithTruncation(millisecond).
         let millisecond = args
             .get_or_undefined(3)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+            .map_or(Ok::<u16, JsError>(0), |v| {
+                let finite = v.to_finitef64(context)?;
+                Ok(finite.as_integer_with_truncation::<u16>())
+            })?;
+
         // 6. If microsecond is undefined, set microsecond to 0; else set microsecond to ? ToIntegerWithTruncation(microsecond).
         let microsecond = args
             .get_or_undefined(4)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+            .map_or(Ok::<u16, JsError>(0), |v| {
+                let finite = v.to_finitef64(context)?;
+                Ok(finite.as_integer_with_truncation::<u16>())
+            })?;
+
         // 7. If nanosecond is undefined, set nanosecond to 0; else set nanosecond to ? ToIntegerWithTruncation(nanosecond).
         let nanosecond = args
             .get_or_undefined(5)
-            .map_or(Ok(0), |v| to_integer_with_truncation(v, context))?;
+            .map_or(Ok::<u16, JsError>(0), |v| {
+                let finite = v.to_finitef64(context)?;
+                Ok(finite.as_integer_with_truncation::<u16>())
+            })?;
 
-        let inner =
-            PlainTimeInner::new(hour, minute, second, millisecond, microsecond, nanosecond)?;
+        let inner = PlainTimeInner::new(
+            hour.into(),
+            minute.into(),
+            second.into(),
+            millisecond.into(),
+            microsecond.into(),
+            nanosecond.into(),
+        )?;
 
         // 8. Return ? CreateTemporalTime(hour, minute, second, millisecond, microsecond, nanosecond, NewTarget).
         create_temporal_time(inner, Some(new_target), context).map(Into::into)
@@ -701,33 +723,57 @@ pub(crate) fn to_partial_time_record(
 ) -> JsResult<PartialTime> {
     let hour = partial_object
         .get(js_string!("hour"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
-        .transpose()?;
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<u8, JsError>(finite.as_integer_with_truncation::<u8>())
+        })
+        .transpose()?
+        .map(Into::into);
 
     let minute = partial_object
         .get(js_string!("minute"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
-        .transpose()?;
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<u8, JsError>(finite.as_integer_with_truncation::<u8>())
+        })
+        .transpose()?
+        .map(Into::into);
 
     let second = partial_object
         .get(js_string!("second"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
-        .transpose()?;
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<u8, JsError>(finite.as_integer_with_truncation::<u8>())
+        })
+        .transpose()?
+        .map(Into::into);
 
     let millisecond = partial_object
         .get(js_string!("millisecond"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
-        .transpose()?;
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<u16, JsError>(finite.as_integer_with_truncation::<u16>())
+        })
+        .transpose()?
+        .map(Into::into);
 
     let microsecond = partial_object
         .get(js_string!("microsecond"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
-        .transpose()?;
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<u16, JsError>(finite.as_integer_with_truncation::<u16>())
+        })
+        .transpose()?
+        .map(Into::into);
 
     let nanosecond = partial_object
         .get(js_string!("nanosecond"), context)?
-        .map(|v| super::to_integer_if_integral(v, context))
-        .transpose()?;
+        .map(|v| {
+            let finite = v.to_finitef64(context)?;
+            Ok::<u16, JsError>(finite.as_integer_with_truncation::<u16>())
+        })
+        .transpose()?
+        .map(Into::into);
 
     Ok(PartialTime {
         hour,
diff --git a/core/engine/src/builtins/temporal/plain_year_month/mod.rs b/core/engine/src/builtins/temporal/plain_year_month/mod.rs
index 7f6349cec40..4a075a21c5a 100644
--- a/core/engine/src/builtins/temporal/plain_year_month/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_year_month/mod.rs
@@ -13,7 +13,8 @@ use crate::{
     property::Attribute,
     realm::Realm,
     string::StaticJsStrings,
-    Context, JsArgs, JsData, JsNativeError, JsObject, JsResult, JsString, JsSymbol, JsValue,
+    Context, JsArgs, JsData, JsError, JsNativeError, JsObject, JsResult, JsString, JsSymbol,
+    JsValue,
 };
 use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
@@ -170,26 +171,40 @@ impl BuiltInConstructor for PlainYearMonth {
                 .into());
         }
 
-        let day = args.get_or_undefined(3);
         // 2. If referenceISODay is undefined, then
-        let ref_day = if day.is_undefined() {
-            // a. Set referenceISODay to 1𝔽.
-            None
-        } else {
-            // 6. Let ref be ? ToIntegerWithTruncation(referenceISODay).
-            Some(super::to_integer_with_truncation(day, context)?)
-        };
-
+        // a. Set referenceISODay to 1𝔽.
         // 3. Let y be ? ToIntegerWithTruncation(isoYear).
-        let y = super::to_integer_with_truncation(args.get_or_undefined(0), context)?;
+        let y = args
+            .get_or_undefined(0)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<i32>();
+
         // 4. Let m be ? ToIntegerWithTruncation(isoMonth).
-        let m = super::to_integer_with_truncation(args.get_or_undefined(1), context)?;
+        let m = args
+            .get_or_undefined(1)
+            .to_finitef64(context)?
+            .as_integer_with_truncation::<i32>();
+
         // 5. Let calendar be ? ToTemporalCalendarSlotValue(calendarLike, "iso8601").
         let calendar = to_temporal_calendar_slot_value(args.get_or_undefined(2))?;
 
+        // 6. Let ref be ? ToIntegerWithTruncation(referenceISODay).
+        let ref_day = args
+            .get_or_undefined(3)
+            .map(|v| {
+                let finite = v.to_finitef64(context)?;
+                Ok::<u8, JsError>(finite.as_integer_with_truncation::<u8>())
+            })
+            .transpose()?;
+
         // 7. Return ? CreateTemporalYearMonth(y, m, calendar, ref, NewTarget).
-        let inner =
-            InnerYearMonth::new_with_overflow(y, m, ref_day, calendar, ArithmeticOverflow::Reject)?;
+        let inner = InnerYearMonth::new_with_overflow(
+            y,
+            m,
+            ref_day.map(Into::into),
+            calendar,
+            ArithmeticOverflow::Reject,
+        )?;
 
         create_temporal_year_month(inner, Some(new_target), context)
     }
@@ -219,22 +234,38 @@ impl PlainYearMonth {
                 let overflow = get_option(&options, js_string!("overflow"), context)?
                     .unwrap_or(ArithmeticOverflow::Constrain);
 
+                let year = item
+                    .get_v(js_string!("year"), context)?
+                    .map(|v| {
+                        let finite = v.to_finitef64(context)?;
+                        Ok::<i32, JsError>(finite.as_integer_with_truncation::<i32>())
+                    })
+                    .transpose()?
+                    .unwrap_or_default();
+
+                let month = item
+                    .get_v(js_string!("month"), context)?
+                    .map(|v| {
+                        let finite = v.to_finitef64(context)?;
+                        Ok::<i32, JsError>(finite.as_integer_with_truncation::<i32>())
+                    })
+                    .transpose()?
+                    .unwrap_or_default();
+
+                let ref_day = item
+                    .get_v(js_string!("day"), context)?
+                    .map(|v| {
+                        let finite = v.to_finitef64(context)?;
+                        Ok::<i32, JsError>(finite.as_integer_with_truncation::<i32>())
+                    })
+                    .transpose()?;
+
                 // a. Let calendar be ? ToTemporalCalendar(item).
                 let calendar = to_temporal_calendar_slot_value(args.get_or_undefined(1))?;
                 InnerYearMonth::new_with_overflow(
-                    super::to_integer_with_truncation(
-                        &item.get_v(js_string!("year"), context)?,
-                        context,
-                    )?,
-                    super::to_integer_with_truncation(
-                        &item.get_v(js_string!("month"), context)?,
-                        context,
-                    )?,
-                    super::to_integer_with_truncation(
-                        &item.get_v(js_string!("day"), context)?,
-                        context,
-                    )
-                    .ok(),
+                    year,
+                    month,
+                    ref_day.map(Into::into),
                     calendar,
                     overflow,
                 )?