Last name Thahan (Thahan 
) , all over the world, is a very rare family name. The surname Thahan is characteristic of Thailand, where it is a rare surname, the United Kingdom, where it is an extremely rare surname, and the United States. In absolute terms, it is the most numerous in Thailand, India, and the United Kingdom. Very seldom, Thahan is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thahan | Philippines, Thailand, United Kingdom, United States, India |