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, France, United States, Uruguay, Italy |
| Piastre | Uruguay, Brazil, United States |