Family name Ratus (Rato 
, Ratus 
, Ratificar 
) , around the world, is a common last name. The last name Ratus is characteristic of Portugal, where it is quite a common surname, Botswana, where it is quite a rare surname, and Libya. Not in comparison with a country's population, it is the most numerous in Portugal, Philippines, and Indonesia. Likewise, Ratus is the forename as well as the last name.