Surname Piastre (Piastra 
, Piastre 
) , globally, is a rare last name. The last name Piastre is characteristic of Uruguay, where it is quite a rare surname, Italy, where it is a rare surname, and France. Very seldom, Piastre is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Piastra | Belgium, Italy, Uruguay, United States, France |
| Piastre | United States, Brazil, Uruguay |