diff --git a/vyper/builtins/functions.py b/vyper/builtins/functions.py
index 915f10ede3..af965afe0a 100644
--- a/vyper/builtins/functions.py
+++ b/vyper/builtins/functions.py
@@ -1247,7 +1247,9 @@ def build_IR(self, expr, args, kwargs, context):
         to, value = args
         gas = kwargs["gas"]
         context.check_is_not_constant("send ether", expr)
-        return IRnode.from_list(["assert", ["call", gas, to, value, 0, 0, 0, 0]])
+        return IRnode.from_list(
+            ["assert", ["call", gas, to, value, 0, 0, 0, 0]], error_msg="send failed"
+        )
 
 
 class SelfDestruct(BuiltinFunction):