diff --git a/sqlite_utils/utils.py b/sqlite_utils/utils.py
index c2a7c91..b719b01 100644
--- a/sqlite_utils/utils.py
+++ b/sqlite_utils/utils.py
@@ -29,7 +29,7 @@ SPATIALITE_PATHS = (
 )
 
 
-def find_spatialite() -> str:
+def find_spatialite() -> Optional[str]:
     """
     The ``find_spatialite()`` function searches for the `SpatiaLite <https://www.gaia-gis.it/fossil/libspatialite/index>`__ SQLite extension in some common places. It returns a string path to the location, or ``None`` if SpatiaLite was not found.