diff --git a/contrib/pyln-client/pyln/client/lightning.py b/contrib/pyln-client/pyln/client/lightning.py
index b76ad2843..12759d694 100644
--- a/contrib/pyln-client/pyln/client/lightning.py
+++ b/contrib/pyln-client/pyln/client/lightning.py
@@ -990,7 +990,7 @@ class LightningRpc(UnixDomainSocketRpc):
 
     def pay(self, bolt11, msatoshi=None, label=None, riskfactor=None,
             maxfeepercent=None, retry_for=None,
-            maxdelay=None, exemptfee=None, exclude=[]):
+            maxdelay=None, exemptfee=None, exclude=None):
         """
         Send payment specified by {bolt11} with {msatoshi}
         (ignored if {bolt11} has an amount), optional {label}