diff --git a/databroker/headersource/sqlite.py b/databroker/headersource/sqlite.py
index 534f7b61e..e633128a0 100644
--- a/databroker/headersource/sqlite.py
+++ b/databroker/headersource/sqlite.py
@@ -88,7 +88,7 @@ def __init__(self, dirpath):
     def reconnect(self):
         for fn in os.listdir(self._dirpath):
             # Cache connections to every sqlite file.
-            match = re.match('([0-9a-z-]+)\.sqlite', fn)
+            match = re.match(r'([0-9a-z-]+)\.sqlite', fn)
             if match is None:
                 # skip unrecognized file
                 continue