Family name Ong-Hay (Ong-Hay 
) , worldwide, is a very rare last name. The cognomen Ong-Hay is habitual in Philippines, where it is a very rare surname, and the United States, where it is an extremely rare surname. Parts of the name also exists independently as a last name Ong, and a first name Hay.
| VARIANT | COUNTRY |
|---|---|
| Ong-Hay | United States, Philippines |