Cognomen Gilfilan (Gilfilan 
) , throughout the world, is a very rare family name. The cognomen Gilfilan is habitual in Philippines, where it is a very rare surname, the United Kingdom, where it is an extremely rare surname, and the United States. Much less frequently, Gilfilan is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gilfilan | United Kingdom, United States, Philippines |