Cognomen Iljaš (Иляш 
, Iljaš 
) , all over the world, is a rare last name. The last name Iljaš is characteristic of Slovenia, where it is quite a rare surname, Croatia, where it is a rare surname, and Kyrgyzstan, where it is a very rare surname. Not in comparison with a country's population, it is commonest in Russia, Croatia, and Slovenia. Also, Iljaš is the forename as well as the last name.