Family name Phomthavong (Phomthavong 
) , in the entire world, is a rare cognomen. The last name Phomthavong is habitual in Laos, where it is quite a common surname, Canada, where it is a very rare surname, and the United States, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Phomthavong | United States, Laos, Canada |