Cognomen Sayyavong (Sayyavong 
) , across the world, is quite a rare last name. The cognomen Sayyavong is characteristic of South-eastern Asia, particularly Laos, where it is quite a common surname, and Thailand, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Sayyavong | Laos, Thailand |
Sisamai, Sonekeo, Somchay, Kaysone, Tingkham, Naphalay, Vangding, Soulisanh, Phonephaivanh, and Viphaphone