Mainz (electoral district)
Mainz is an electoral constituency represented in the Bundestag. It elects one member via first-past-the-post voting. Under the current constituency numbering system, it is designated as constituency 204. It is located in eastern Rhineland-Palatinate, comprising the city of Mainz and the northern part of the Mainz-Bingen district.
Mainz was created for the inaugural 1949 federal election. Whilst the Christian Democratic Union won the plurality in the 2025 election, under the new voting system, their candidate did not actually win a seat in the Bundestag. This was due to the distribution of seats won by the CDU being decided by the first vote percentage of each winning CDU candidate, determining who took the seats. As the CDU candidate got a low vote of 27.3%, the seat will remain vacant throughout the 21st Bundestag.
Geography
Mainz is located in eastern Rhineland-Palatinate. As of the 2021 federal election, it comprises the independent city of Mainz as well as the municipalities of Bingen am Rhein, Budenheim, and Ingelheim am Rhein and the Verbandsgemeinden of Gau-Algesheim, Nieder-Olm, and Rhein-Nahe from the Mainz-Bingen district.History
Mainz was created in 1949. In the 1949 election, it was Rhineland-Palatinate constituency 9 in the numbering system. In the 1953 through 1976 elections, it was number 156. In the 1980 through 1998 elections, it was number 154. In the 2002 election, it was number 208. In the 2005 election, it was number 207. In the 2009 and 2013 elections, it was number 206. In the 2017 and 2021 elections, it was number 205. From the 2025 election, it has been number 204.Originally, the constituency comprised the city of Mainz and the districts of Bingen and Landkreis Mainz excluding the Amtsgerichtsbezirk of Oppenheim. In the 1972 through 2013 elections, it acquired a configuration very similar to its current borders, but including the Verbandsgemeinde of Sprendlingen-Gensingen. It acquired its current borders in the 2017 election.
| Election | Name | Borders | |
| 1949 | Mainz |
| |
| 1953 | 156 | Mainz | |
| 1957 | 156 | Mainz | |
| 1961 | 156 | Mainz | |
| 1965 | 156 | Mainz | |
| 1969 | 156 | Mainz | |
| 1972 | 156 | Mainz | |
| 1976 | 156 | Mainz | |
| 1980 | 154 | Mainz | |
| 1983 | 154 | Mainz | |
| 1987 | 154 | Mainz | |
| 1990 | 154 | Mainz | |
| 1994 | 154 | Mainz | |
| 1998 | 154 | Mainz | |
| 2002 | 208 | Mainz | |
| 2005 | 207 | Mainz | |
| 2009 | 206 | Mainz | |
| 2013 | 206 | Mainz | |
| 2017 | 205 | Mainz | |
| 2021 | 205 | Mainz | |
| 2025 | 204 | Mainz |