Family name Siefu (Siefu 
) , across the world, is a rare cognomen. The cognomen Siefu is habitual in Ethiopia, where it is a rare surname, Canada, where it is an extremely rare surname, and the United States. Much less frequently, Siefu is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Siefu | Nigeria, Ethiopia, Canada, United States |