diff --git a/src/aiomail/client.py b/src/aiomail/client.py
index 5932139..8d06419 100644
--- a/src/aiomail/client.py
+++ b/src/aiomail/client.py
@@ -245,12 +245,18 @@ class IMAPClient:
         return None
 
     async def mark_seen(self, email_id: int) -> bool:
-        """flag a message as read without deleting it"""
+        """flag a message as read without deleting it
+
+        aioimaplib does not apply its own timeout to the UID STORE command path, so the
+        use_uid=True call is wrapped here to bound it the same as the non-uid path.
+        """
         if not await self.ensure_connection():
             return False
         try:
             if self.use_uid:
-                result, _ = await self._mail.uid("store", str(email_id), "+FLAGS", "(\\Seen)")
+                result, _ = await asyncio.wait_for(
+                    self._mail.uid("store", str(email_id), "+FLAGS", "(\\Seen)"), self.timeout
+                )
             else:
                 result, _ = await self._mail.store(str(email_id), "+FLAGS", "(\\Seen)")
             return result == "OK"