Surname Idelfonsa (Idelfonsa 
) , across the world, is a rare cognomen. The surname Idelfonsa is characteristic of Mexico, where it is a rare surname, Spain, and the Dominican Republic. Likewise, Idelfonsa is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Idelfonsa | Paraguay, Spain, Mexico, Argentina, Peru |