diff --git a/betterproto2/src/betterproto2/__init__.py b/betterproto2/src/betterproto2/__init__.py
index 98221ec..54cb588 100644
--- a/betterproto2/src/betterproto2/__init__.py
+++ b/betterproto2/src/betterproto2/__init__.py
@@ -1152,6 +1152,10 @@ def _from_dict_init(cls, mapping: Mapping[str, Any] | Any, *, ignore_unknown_fie
 
             if meta.proto_type == TYPE_MESSAGE:
                 if meta.repeated:
+                    if value is None:
+                        raise TypeError(
+                            f"Cannot use None for repeated field '{field_name}'; expected an iterable value."
+                        )
                     value = [_value_from_dict(item, meta, field_cls, ignore_unknown_fields) for item in value]
                 else:
                     value = _value_from_dict(value, meta, field_cls, ignore_unknown_fields)
@@ -1170,6 +1174,8 @@ def _from_dict_init(cls, mapping: Mapping[str, Any] | Any, *, ignore_unknown_fie
                 }
 
             elif meta.repeated:
+                if value is None:
+                    raise TypeError(f"Cannot use None for repeated field '{field_name}'; expected an iterable value.")
                 value = [_value_from_dict(item, meta, field_cls, ignore_unknown_fields) for item in value]
 
             else:
diff --git a/betterproto2/uv.lock b/betterproto2/uv.lock
index d596e1f..470fa03 100644
--- a/betterproto2/uv.lock
+++ b/betterproto2/uv.lock
@@ -1581,15 +1581,15 @@ wheels = [
 
 [[package]]
 name = "pyright"
-version = "1.1.407"
+version = "1.1.410"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "nodeenv" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/a6/1b/0aa08ee42948b61745ac5b5b5ccaec4669e8884b53d31c8ec20b2fcd6b6f/pyright-1.1.407.tar.gz", hash = "sha256:099674dba5c10489832d4a4b2d302636152a9a42d317986c38474c76fe562262", size = 4122872, upload-time = "2025-10-24T23:17:15.145Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/10/53/e4d8ea1391bd4355231be6f91bf239479aa0014260ed3fb5526eeb12a1f2/pyright-1.1.410.tar.gz", hash = "sha256:07a073b8ba6749826773c1269773efa11b93440d9a6aa60419d9a3172d6dc488", size = 4062013, upload-time = "2026-06-01T17:35:48.894Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/dc/93/b69052907d032b00c40cb656d21438ec00b3a471733de137a3f65a49a0a0/pyright-1.1.407-py3-none-any.whl", hash = "sha256:6dd419f54fcc13f03b52285796d65e639786373f433e243f8b94cf93a7444d21", size = 5997008, upload-time = "2025-10-24T23:17:13.159Z" },
+    { url = "https://files.pythonhosted.org/packages/d7/33/288b5868fa00846dacf249633719d747893e54aebd196b9968ac1878a5d3/pyright-1.1.410-py3-none-any.whl", hash = "sha256:5e961bed37cacf96b3f7cd7b1da39b350a9239aa2e69138d0e88f728cfaf296c", size = 6082448, upload-time = "2026-06-01T17:35:46.387Z" },
 ]
 
 [[package]]