Family name Guaillasaca Berrezueta (Guaillasaca Berrezueta 
) , around the globe, is a very rare cognomen. The surname Guaillasaca Berrezueta is characteristic of Ecuador, where it is a very rare surname, and Spain, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Guaillasaca Berrezueta | Spain, Ecuador |