| Bad Sauerbrunn | |
| Native Name: | Sauabrunn |
| Pushpin Map: | Austria |
| Pushpin Mapsize: | 270 |
| Pushpin Map Caption: | Location within Austria |
| Coordinates: | 47.7667°N 36°W |
| Subdivision Type: | Country |
| Subdivision Name: | Austria |
| Subdivision Type1: | State |
| Subdivision Name1: | Burgenland |
| Subdivision Type2: | District |
| Subdivision Name2: | Mattersburg |
| Parts Style: | para |
| Leader Title: | Mayor |
| Leader Name: | Gerhard Hutter |
| Elevation M: | 280 |
| Population Density Km2: | auto |
| Timezone: | CET |
| Timezone Dst: | CEST |
| Utc Offset: | +1 |
| Utc Offset Dst: | +2 |
| Postal Code Type: | Postal code |
| Postal Code: | 7202 |
| Area Code Type: | Area code |
| Website: | www.bad-sauerbrunn.at (in German) |
Bad Sauerbrunn (pronounced as /de/; until 1987, Sauerbrunn; Hungarian: Savanyúkút; Croatian: Kisela voda; Central Bavarian: Sauabrunn) is the name of a mineral spa and the town in which it is located, in the district of Mattersburg in the Austrian state of Burgenland. The spa was used in ancient times by the Romans and was re-opened in 1847.[1] The town, formerly called Savanyúkút, was part of German-speaking western Hungary until that territory became part of Austria in 1920. In 1921 Sauerbrunn, became the provisional capital of the newly formed federal state of Burgenland until 1925, when the seat of government moved to Eisenstadt.