Cognomen Tarnauskas (Tarnauskas 
) , across the world, is a rare last name. The surname Tarnauskas is habitual in Lithuania, where it is quite a rare surname, Croatia, where it is a very rare surname, and the United States, where it is an extremely rare surname. Measured by absolute frequency, it is commonest in Lithuania, the United States, and the United Kingdom.
| VARIANT | COUNTRY |
|---|---|
| Tarnauskas | United States, Lithuania, United Kingdom, Croatia |