Family name Koosakulrat (Koosakulrat 
) , around the world, is a very rare surname. The last name Koosakulrat is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Koosakulrat | Thailand |
Warisara, Mathuraya, Jittrawadee, and Treetippaya