The 2021 Swiss same-sex marriage referendum was a facultative referendum held in Switzerland on 26 September 2021 about an amendment to the Civil Code to legalise marriage between people of the same sex, as well as adoption rights for same-sex couples and access to assisted reproductive technology for lesbian couples. The amendment was called "marriage for all" (Ehe für alle, Mariage pour tous, Matrimonio per tutti, Lètg per tuts) in Swiss public discourse.
64.1% of voters and all cantons supported the amendment, which entered into force on 1 July 2022.[1] The vote made Switzerland the 29th country to legalise same-sex marriage. When the vote took place, Switzerland was one of few countries in Western Europe yet to grant same-sex couples the right to marry.[2]