Cognomen Gastaaduy (Gastaaduy 
) , all around the world, is a very rare surname. The family name Gastaaduy is characteristic of Latin America and the Caribbean, particularly Peru, where it is a very rare surname. Very seldom, Gastaaduy is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gastaaduy | Peru |