diff --git a/CHANGELOG.md b/CHANGELOG.md
index 96067e3..f4c4426 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 # 1.14.4 (Unreleased)
 
 * `msgpack`: Now uses string encoding instead of float encoding for a whole number that is too large to fit in any of MessagePack's integer types.
+* `function/stdlib`: Type conversion functions (constructed with `MakeToFunc`) can now convert null values of unknown type into null values of the target type, rather than returning an unknown value in that case.
 
 # 1.14.3 (February 29, 2024)
 
diff --git a/cty/function/stdlib/conversion.go b/cty/function/stdlib/conversion.go
index 5d06a45..406dea2 100644
--- a/cty/function/stdlib/conversion.go
+++ b/cty/function/stdlib/conversion.go
@@ -30,8 +30,9 @@ func MakeToFunc(wantTy cty.Type) function.Function {
 				// messages to be more appropriate for an explicit type
 				// conversion, whereas the cty function system produces
 				// messages aimed at _implicit_ type conversions.
-				Type:      cty.DynamicPseudoType,
-				AllowNull: true,
+				Type:             cty.DynamicPseudoType,
+				AllowNull:        true,
+				AllowDynamicType: true,
 			},
 		},
 		Type: func(args []cty.Value) (cty.Type, error) {
diff --git a/cty/function/stdlib/conversion_test.go b/cty/function/stdlib/conversion_test.go
index c25cec7..41796c8 100644
--- a/cty/function/stdlib/conversion_test.go
+++ b/cty/function/stdlib/conversion_test.go
@@ -56,6 +56,12 @@ func TestTo(t *testing.T) {
 			cty.NullVal(cty.Number),
 			``,
 		},
+		{
+			cty.NullVal(cty.DynamicPseudoType),
+			cty.Number,
+			cty.NullVal(cty.Number),
+			``,
+		},
 		{
 			cty.UnknownVal(cty.Bool),
 			cty.String,