diff --git a/autoapi/_objects.py b/autoapi/_objects.py
index 99e0b12e..324db121 100644
--- a/autoapi/_objects.py
+++ b/autoapi/_objects.py
@@ -280,7 +280,7 @@ def __init__(self, *args, **kwargs):
 
         Can be only be: async.
         """
-        self.overloads: list[tuple[str, str]] = [
+        self.overloads: list[tuple[str, str | None]] = [
             (_format_args(args), return_annotation)
             for args, return_annotation in self.obj["overloads"]
         ]
diff --git a/docs/changes/523.bugfix.rst b/docs/changes/523.bugfix.rst
new file mode 100644
index 00000000..6a0b232e
--- /dev/null
+++ b/docs/changes/523.bugfix.rst
@@ -0,0 +1 @@
+Fix `PythonFunction.overloads` typing when source code overload(s) do not provide a return type