diff --git a/src/nooa/storage/serialization.py b/src/nooa/storage/serialization.py
index b3e612a72..e58835712 100644
--- a/src/nooa/storage/serialization.py
+++ b/src/nooa/storage/serialization.py
@@ -154,6 +154,10 @@ def _serialize(value: Any, allowlist: set[str]) -> Any:
             serialized = _serialize(getattr(value, field_name), allowlist)
             if serialized is not SKIP:
                 data[field_name] = serialized
+        for field_name, extra in (value.model_extra or {}).items():
+            serialized = _serialize(extra, allowlist)
+            if serialized is not SKIP:
+                data[field_name] = serialized
         return {"__type__": _PYDANTIC, "__class__": fqn, "data": data}
 
     # 6. Dataclasses
@@ -235,6 +239,8 @@ def _deserialize_envelope(blob: dict[str, Any], allowlist: set[str]) -> Any:
         # Deserialize nested envelopes first (e.g. dataclass/snapshotable
         # fields), then let Pydantic validate the reconstructed objects.
         deserialized_data = {k: _deserialize(v, allowlist) for k, v in data.items()}
+        if cls.model_config.get("extra") == "allow":
+            return cls.model_validate(deserialized_data)
         # Filter to known fields for lenient restoration (handles extra="forbid"
         # models that would reject extra fields from schema drift).
         known_fields = set(cls.model_fields)
diff --git a/tests/storage/test_serialization.py b/tests/storage/test_serialization.py
index d6d5dd858..c8d57fbc7 100644
--- a/tests/storage/test_serialization.py
+++ b/tests/storage/test_serialization.py
@@ -15,6 +15,7 @@
 import pytest
 from pydantic import BaseModel, ConfigDict
 
+from nooa.config.model_config import ModelConfig
 from nooa.errors.storage import DeserializationError, SerializationError
 from nooa.storage.markers import snapshotable
 from nooa.storage.serialization import SKIP, deserialize, serialize
@@ -170,7 +171,39 @@ def test_SKIP_sentinel_identity(self):
 
 
 class TestPydantic:
+    def test_model_config_preserves_provider_extras(self):
+        """Snapshot round trips retain provider options stored as allowed model extras."""
+        model = ModelConfig(model_name="test", num_retries=7, custom={"stops": ("a", "b")})
+        blob, allowlist = serialize(model)
+        restored = deserialize(blob, allowlist)
+        assert restored == model
+        assert restored.model_extra == model.model_extra
+
+    def test_extra_values_use_recursive_serialization(self):
+        """Nested dataclasses and snapshotable values in extras retain their types."""
+        model = ModelConfig(custom={"point": Point(1, 2), "config": Config("localhost")})
+        blob, allowlist = serialize(model)
+        restored = deserialize(blob, allowlist)
+        assert restored.model_extra["custom"]["point"] == Point(1, 2)
+        config = restored.model_extra["custom"]["config"]
+        assert isinstance(config, Config)
+        assert config.host == "localhost"
+
+    def test_nested_extra_class_requires_allowlist(self):
+        """Allowing extra fields does not bypass the nested-class restoration allowlist."""
+        model = ModelConfig(custom=Point(1, 2))
+        blob, allowlist = serialize(model)
+        with pytest.raises(DeserializationError, match="not in the allowlist"):
+            deserialize(blob, allowlist - {f"{Point.__module__}.Point"})
+
+    def test_nosnapshot_extra_is_skipped(self):
+        """Opted-out extra values are skipped without losing serializable sibling options."""
+        model = ModelConfig(custom=_NoSnapshotThing(), num_retries=7)
+        blob, allowlist = serialize(model)
+        assert deserialize(blob, allowlist).model_extra == {"num_retries": 7}
+
     def test_simple_model_roundtrip(self):
+        """Ordinary declared Pydantic fields still survive a snapshot round trip."""
         m = MyModel(name="test", value=42)
         blob, al = serialize(m)
         assert blob["__type__"] == "pydantic"