Last name קאסו (Caso 
, קאסו 
) , worldwide, is a common surname. The family name קאסו is habitual in Aland Islands, where it is quite a common surname, Peru, and Italy, where it is quite a rare surname. Measured by absolute frequency, the name is most common in Italy, Peru, and the United States. Much less frequently, קאסו is the forename as well as the last name.