diff --git a/setup.py b/setup.py
index 91d5d93..1672ea5 100644
--- a/setup.py
+++ b/setup.py
@@ -26,7 +26,7 @@ setup(
         "logbook",
         "peewee",
         "janus",
-        "prompt_toolkit>2<3",
+        "prompt_toolkit>2<4",
         "typing;python_version<'3.5'",
         "matrix-nio[e2e] >= 0.4.1"
     ],