Last name Herdo (Herd 
, Herdo 
, Hearth 
) , around the globe, is a common surname. The cognomen Herdo is habitual in New Zealand, where it is quite a common surname, the United Kingdom, where it is quite a rare surname, and Australia. Not in comparison with a country's population, it most frequently occurs in the United States, the United Kingdom, and New Zealand. Much less frequently, Herdo is the forename as well as the last name.