diff --git a/msgspec/_json_schema.py b/msgspec/_json_schema.py
index be506e3f..f73c97a3 100644
--- a/msgspec/_json_schema.py
+++ b/msgspec/_json_schema.py
@@ -310,6 +310,13 @@ def to_schema(self, t: mi.Type, check_ref: bool = True) -> dict[str, Any]:
             if t.min_length is not None:
                 schema["minProperties"] = t.min_length
         elif isinstance(t, mi.UnionType):
+            # don't wrap simple optionals in an anyOf
+            if len(t.types) == 2 and t.includes_none:
+                return (
+                    self.to_schema(t.types[0])
+                    if not isinstance(t.types[0], mi.NoneType)
+                    else self.to_schema(t.types[1])
+                )
             structs = {}
             other = []
             tag_field = None
diff --git a/tests/test_schema.py b/tests/test_schema.py
index e1b9df3c..c848fa6d 100644
--- a/tests/test_schema.py
+++ b/tests/test_schema.py
@@ -309,7 +309,7 @@ class Polygon(msgspec.Struct):
                         "items": {"$ref": "#/$defs/Point"},
                     },
                     "name": {
-                        "anyOf": [{"type": "string"}, {"type": "null"}],
+                        "type": "string",
                         "default": None,
                     },
                     "metadata": {
@@ -722,7 +722,7 @@ class Polygon:
                         "items": {"$ref": "#/$defs/Point"},
                     },
                     "name": {
-                        "anyOf": [{"type": "string"}, {"type": "null"}],
+                        "type": "string",
                         "default": None,
                     },
                     "metadata": {