diff --git a/vyper/builtins/functions.py b/vyper/builtins/functions.py
index 685d832c01..e8e001306c 100644
--- a/vyper/builtins/functions.py
+++ b/vyper/builtins/functions.py
@@ -1093,7 +1093,7 @@ def fetch_call_return(self, node):
         revert_on_failure = kwargz.get("revert_on_failure")
         revert_on_failure = revert_on_failure.value if revert_on_failure is not None else True
 
-        if outsize is None:
+        if outsize is None or outsize.value == 0:
             if revert_on_failure:
                 return None
             return BoolT()