diff --git a/Project.toml b/Project.toml
index 477ccc9d..e536a612 100644
--- a/Project.toml
+++ b/Project.toml
@@ -3,7 +3,7 @@ uuid = "80f14c24-f653-4e6a-9b94-39d6b0f70001"
 keywords = ["markov chain monte carlo", "probablistic programming"]
 license = "MIT"
 desc = "A lightweight interface for common MCMC methods."
-version = "3.0.0"
+version = "3.0.1"
 
 [deps]
 BangBang = "198e06fe-97b7-11e9-32a5-e1d131e6ad66"
diff --git a/src/sample.jl b/src/sample.jl
index 563d4652..3bf55083 100644
--- a/src/sample.jl
+++ b/src/sample.jl
@@ -197,7 +197,7 @@ function mcmcsample(
         end
 
         # Run callback.
-        callback === nothing || callback(rng, model, sampler, sample, 1)
+        callback === nothing || callback(rng, model, sampler, sample, state, 1; kwargs...)
 
         # Save the sample.
         samples = AbstractMCMC.samples(sample, model, sampler; kwargs...)
@@ -217,7 +217,7 @@ function mcmcsample(
             sample, state = step(rng, model, sampler, state; kwargs...)
 
             # Run callback.
-            callback === nothing || callback(rng, model, sampler, sample, i)
+            callback === nothing || callback(rng, model, sampler, sample, state, i; kwargs...)
 
             # Save the sample.
             samples = save!!(samples, sample, i, model, sampler; kwargs...)
diff --git a/test/sample.jl b/test/sample.jl
index 00f7ccae..b07387c7 100644
--- a/test/sample.jl
+++ b/test/sample.jl
@@ -292,11 +292,16 @@
     
     @testset "Testing callbacks" begin
         function count_iterations(rng, model, sampler, sample, state, i; iter_array, kwargs...)
-            iter_array[i] = i
+            push!(iter_array, i)
         end
         N = 100
-        it_array = zeros(N)
+        it_array = Float64[]
         sample(MyModel(), MySampler(), N; callback=count_iterations, iter_array=it_array)
         @test it_array == collect(1:N)
+
+        # sampling without predetermined N
+        it_array = Float64[]
+        chain = sample(MyModel(), MySampler(); callback=count_iterations, iter_array=it_array)
+        @test it_array == collect(1:size(chain, 1))
     end
 end