Last name 洪晗 (洪晗 
) , in the world, is a very rare cognomen. The family name 洪晗 is habitual in Eastern Asia, particularly China, where it is an extremely rare surname. More prevalently, 洪晗 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 洪晗 | China |