Cognomen ธรรมรัต (Thammarat 
, ธรรมรัต ) , all around the world, is quite a rare last name. The surname ธรรมรัต is characteristic of Thailand, where it is quite a rare surname, Malaysia, where it is a rare surname, and Norway, where it is a very rare surname. Not in comparison with a country's population, the name is most common in Thailand, Malaysia, and the United States. Also, ธรรมรัต is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thammarat | Norway, China, Malaysia, Thailand, United States |
| ธรรมรัต | Thailand |