diff --git a/distributed/stealing.py b/distributed/stealing.py
index 2c78704ceb6..c32d45481ab 100644
--- a/distributed/stealing.py
+++ b/distributed/stealing.py
@@ -148,7 +148,7 @@ def log(self, msg):
     def add_worker(self, scheduler=None, worker=None):
         self.stealable[worker] = tuple(set() for _ in range(15))
 
-    def remove_worker(self, scheduler: Scheduler, worker: str):
+    def remove_worker(self, scheduler: Scheduler, worker: str) -> None:
         del self.stealable[worker]
 
     def teardown(self):