--- a/src/map/script.cpp
+++ b/src/map/script.cpp
@@ -27559,6 +27559,23 @@ BUILDIN_FUNC(monster_immunity) {
 	return SCRIPT_CMD_SUCCESS;
 }
 
+/**
+ * KafraShop Addon
+ * charid2rid(<char_id>);
+ **/
+BUILDIN_FUNC(charid2rid) {
+	int char_id = script_getnum(st, 2);
+	map_session_data* sd = map_charid2sd(char_id);
+
+	if (sd == nullptr) {
+		script_pushint(st, 0);
+		return SCRIPT_CMD_SUCCESS;
+	}
+
+	script_pushint(st, sd->status.account_id);
+	return SCRIPT_CMD_SUCCESS;
+}
+
 #include <custom/script.inc>
 
 // declarations that were supposed to be exported from npc_chat.cpp
@@ -28336,6 +28353,11 @@ struct script_function buildin_func[] = {
 	BUILDIN_DEF(setprofession_count, "isi"),
 	BUILDIN_DEF(monster_immunity, "ii"),
 
+	/**
+	 * KafraShop: Sabong Event
+	 **/
+	BUILDIN_DEF(charid2rid, "i"),
+
 #include <custom/script_def.inc>
 
 	{nullptr,nullptr,nullptr},