Family name บุญจันทร์ (บุญจันทร์ 
, Boonchan 
, Bunchan 
) , worldwide, is a common surname. The cognomen บุญจันทร์ is habitual in Thailand, where it is quite a common surname, and the United States, where it is an extremely rare surname. Likewise, บุญจันทร์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| บุญจันทร์ | Thailand |
| Boonchan | United Kingdom, Malaysia, Thailand, United States |
| Bunchan | Australia, Thailand, United Kingdom, United States, India |
| Boonjan | Malaysia, Thailand, United States |