Family name Біллі (Billi 
, Біллі 
) , all around the world, is quite a common surname. The cognomen Біллі is characteristic of Southern Europe, particularly San Marino, where it is quite a common surname, Italy, where it is quite a rare surname, and Greece. Measured by absolute frequency, this name is the most popular in Italy, India, and Indonesia. Also, Біллі is the forename as well as the last name.