Cognomen Ильера (Illera 
, Ильера 
) , all around the world, is quite a rare last name. The family name Ильера is habitual in Colombia, where it is quite a rare surname, Spain, where it is a rare surname, and Austria. Measured by absolute frequency, this name is the most popular in Colombia, Spain, and the United States. Much less frequently, Ильера is the forename as well as the last name.