Cognomen Гайлюс (Gailius 
, Гайлюс 
) , across the world, is quite a rare surname. The cognomen Гайлюс is habitual in Lithuania, where it is quite a common surname, Latvia, where it is a rare surname, and South Korea. In absolute terms, the name is most common in Lithuania, South Korea, and Poland. Very seldom, Гайлюс is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gailius | Romania, South Korea, United States, Poland, Lithuania |
| Гайлюс | Ukraine, Russia |
| гайлюс, антанас Lithuanian poet, LT (b. 1951) |
|