Family name ปทุมสาย (ปทุมสาย 
, Patumsai , Pathumsai ) , worldwide, is a very rare surname. The surname ปทุมสาย is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname. Very seldom, ปทุมสาย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Phathumsai, ปทุมสาย, Patumsai, Pathumsai | Thailand |