Family name Ngamphongsai (Ngamphongsai 
) , globally, is a very rare last name. The last name Ngamphongsai is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. More frequently, Ngamphongsai is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Ngamphongsai | Thailand |