diff --git a/lightningd/jsonrpc.c b/lightningd/jsonrpc.c
index dd607ecb1..24f5e9566 100644
--- a/lightningd/jsonrpc.c
+++ b/lightningd/jsonrpc.c
@@ -970,9 +970,9 @@ static bool json_tok_command(struct command *cmd, const char *name,
 	if (cmd->json_cmd)
 		return (*out = tok);
 
-	command_fail(cmd, JSONRPC2_INVALID_PARAMS,
-		     "'%s' of '%.*s' is invalid",
-		     name, tok->end - tok->start, buffer + tok->start);
+	command_fail(cmd, JSONRPC2_METHOD_NOT_FOUND,
+		     "Unknown command '%.*s'",
+		     tok->end - tok->start, buffer + tok->start);
 	return false;
 }
 
diff --git a/tests/test_misc.py b/tests/test_misc.py
index 8d91b5251..f45781aaa 100644
--- a/tests/test_misc.py
+++ b/tests/test_misc.py
@@ -1079,7 +1079,7 @@ def test_check_command(node_factory):
     l1.rpc.check(command_to_check='help', command='check')
     # Note: this just checks form, not whether it's valid!
     l1.rpc.check(command_to_check='help', command='badcommand')
-    with pytest.raises(RpcError, match=r'is invalid'):
+    with pytest.raises(RpcError, match=r'Unknown command'):
         l1.rpc.check(command_to_check='badcommand')
     with pytest.raises(RpcError, match=r'unknown parameter'):
         l1.rpc.check(command_to_check='help', badarg='x')