Cognomen Haaro (Haaro 
) , throughout the world, is a rare last name. The family name Haaro is habitual in Finland, where it is quite a rare surname, Estonia, where it is a rare surname, and the United States, where it is an extremely rare surname. In absolute terms, this name is the most popular in Finland, India, and Estonia. Very seldom, Haaro is the forename as well as the last name.