diff --git a/setup.py b/setup.py
index ae8eb6a9..d3ce43d7 100644
--- a/setup.py
+++ b/setup.py
@@ -59,6 +59,7 @@
         "werkzeug>=2,<3; python_version < '3.8'",
         "werkzeug>=3,<4; python_version >= '3.8'",
         "watchdog>=2,<=4",
+        "phonenumbers>=8.12,<9",
     ],
     # See https://pypi.python.org/pypi?%3Aaction=list_classifiers
     classifiers=[