Last name Santillan Castillo (Santillan Castillo 
) , around the world, is a very rare family name. The surname Santillan Castillo is characteristic of Latin America and the Caribbean, particularly Ecuador, where it is a rare surname, Chile, where it is an extremely rare surname, and Peru.
| VARIANT | COUNTRY |
|---|---|
| Santillan Castillo | Chile, Ecuador, Peru |