Cognomen Ергардт (Erhardt 
, Ергардт 
, Ergardt 
) , in the world, is a common surname. The cognomen Ергардт is habitual in Marshall Islands, where it is a common surname, Germany, where it is quite a rare surname, and Malta. Not in comparison with a country's population, this name is the most popular in Germany, the United States, and Brazil. Very seldom, Ергардт is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Erhardt | Germany, Hungary, United States, Argentina, Brazil |
| Ергардт | Russia, Ukraine |
| Ergardt | Germany, Russia, Estonia, United States |