Family name Iuston (Iuston 
) , in the world, is a very rare last name. The cognomen Iuston is characteristic of Italy, where it is a very rare surname, the United Kingdom, where it is an extremely rare surname, and the United States. Very seldom, Iuston is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Iuston | Brazil, Italy, Canada, United Kingdom, United States |