Cognomen Siplan (Siplan 
) , in the world, is a very rare surname. The family name Siplan is habitual in South-eastern Asia, particularly Philippines, where it is a very rare surname. Very seldom, Siplan is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Siplan | Aland Islands, Spain, Philippines, United States, India |