diff --git a/changes/as-payload-error-lists-float-bigint.polish.md b/changes/as-payload-error-lists-float-bigint.polish.md
new file mode 100644
index 0000000000..cec86be576
--- /dev/null
+++ b/changes/as-payload-error-lists-float-bigint.polish.md
@@ -0,0 +1 @@
+- List floats and bigints in the error for an invalid `@as` payload, since `@as` accepts them.
diff --git a/compiler/ml/UntaggedVariants.md b/compiler/ml/UntaggedVariants.md
index cec70e4975..a3e21a8352 100644
--- a/compiler/ml/UntaggedVariants.md
+++ b/compiler/ml/UntaggedVariants.md
@@ -71,8 +71,8 @@ is the number `1`.
 - Implementation: `ast_untagged_variants.ml:runtime_tag_of_parsetree`,
   `process_constructor_tag`.
 - Tests: fixtures `UntaggedInvalidVariantAsAnnotation.res`
-  ("A variant case annotation @as(...) must be a string, integer, boolean,
-  null, or undefined."), `VariantAsIntegerOutOfRange.res`,
+  ("A variant case annotation @as(...) must be a string, integer, float,
+  bigint, boolean, null, or undefined."), `VariantAsIntegerOutOfRange.res`,
   `UntaggedDuplicatedBsAs.res`; `spec_test` rule 2;
   `tests/tests/src/unboxed_variant_fold_test.res` (`wide`).
 
@@ -140,7 +140,7 @@ The type checker rejects an untagged variant, with
 | Condition | Reason | Fixture |
 | --- | --- | --- |
 | two object cases | At most one case can be an object type. | `UntaggedAtMostOneObject.res` |
-| two cases of one instance class (arrays and tuples share `Array`) | At most one case can be a C type. | `UntaggedAtMostOneInstance.res`, `UntaggedTupleAndArray.res` |
+| two cases of one instance class (arrays and tuples share `Array`) | At most one case can be a C type; for `Array`, an array or tuple type. | `UntaggedAtMostOneInstance.res`, `UntaggedTupleAndArray.res` |
 | two function cases | At most one case can be a function type. | `UntaggedAtMostOneFunction.res` |
 | two string cases | At most one case can be a string type. | `UntaggedAtMostOneString.res` |
 | two number cases (`int` and `float` count together) | At most one case can be a number type (int or float). | `UntaggedAtMostOneNumber.res` |
diff --git a/compiler/ml/ast_untagged_variants.ml b/compiler/ml/ast_untagged_variants.ml
index 37807fd445..cfad02b58a 100644
--- a/compiler/ml/ast_untagged_variants.ml
+++ b/compiler/ml/ast_untagged_variants.ml
@@ -27,8 +27,8 @@ let report_error ppf =
   function
   | InvalidVariantAsAnnotation ->
     fprintf ppf
-      "A variant case annotation @as(...) must be a string, integer, boolean, \
-       null, or undefined."
+      "A variant case annotation @as(...) must be a string, integer, float, \
+       bigint, boolean, null, or undefined."
   | VariantAsIntegerOutOfRange value ->
     fprintf ppf
       "The integer %s in this variant case's @as annotation is out of range."
diff --git a/tests/build_tests/super_errors/expected/UntaggedInvalidVariantAsAnnotation.res.expected b/tests/build_tests/super_errors/expected/UntaggedInvalidVariantAsAnnotation.res.expected
index 85663aa291..6ce8455fc7 100644
--- a/tests/build_tests/super_errors/expected/UntaggedInvalidVariantAsAnnotation.res.expected
+++ b/tests/build_tests/super_errors/expected/UntaggedInvalidVariantAsAnnotation.res.expected
@@ -5,4 +5,4 @@
   1 │ type t = | @as(foo) A | B
   2 │ 
 
-  A variant case annotation @as(...) must be a string, integer, boolean, null, or undefined.
\ No newline at end of file
+  A variant case annotation @as(...) must be a string, integer, float, bigint, boolean, null, or undefined.
\ No newline at end of file