In all the world, Jefferis (Jefferis 
) is a very rare male first name. Much more frequently, Jefferis is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Jefferis | Australia, Canada, United Kingdom, United States, Botswana |
| millis jefferis British Army general, GB (b. 1899) |
|
|
| vaughn jefferis New Zealand equestrian, NZ (b. 1961) |
|