diff --git a/cups/scheduler/cups.socket.in b/cups/scheduler/cups.socket.in
index 3c37d7213..747ea3959 100644
--- a/cups/scheduler/cups.socket.in
+++ b/cups/scheduler/cups.socket.in
@@ -4,6 +4,7 @@ PartOf=cups.service
 [Socket]
 ListenStream=@CUPS_DEFAULT_DOMAINSOCKET@
 RemoveOnStop=on
+ListenStream=631
 
 [Install]
 WantedBy=sockets.target