Surname Chastaigne (Castan 
, Chastaigne 
, Castán 
) , all over the world, is quite a common family name. The surname Chastaigne is habitual in Martinique, where it is a common surname, France, where it is quite a rare surname, and Spain. In absolute terms, it is the most numerous in Mexico, France, and Spain. Much less frequently, Chastaigne is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Castan | Argentina, Spain, France, Mexico, Germany |
| Chastaigne | Martinique, France, United States |
| Castán | Argentina, United States, Spain, Mexico, Brazil |
| Châtain | France |
Chastaigné, Chestnut, Châtaigne, and Kastanja