diff --git a/include/asterisk/manager.h b/include/asterisk/manager.h
index 65aa1fb281..fac8c2bdf1 100644
--- a/include/asterisk/manager.h
+++ b/include/asterisk/manager.h
@@ -262,7 +262,7 @@ struct ast_variable *astman_get_variables(const struct message *m);
 void astman_send_error(struct mansession *s, const struct message *m, char *error);
 
 /*! \brief Send error in manager transaction (with va_args support) */
-void astman_send_error_va(struct mansession *s, const struct message *m, const char *fmt, ...);
+void __attribute__((format(printf, 3, 4))) astman_send_error_va(struct mansession *s, const struct message *m, const char *fmt, ...);
 
 /*! \brief Send response in manager transaction */
 void astman_send_response(struct mansession *s, const struct message *m, char *resp, char *msg);