A legal status acquired by couples who register as civil partners of each other under the Civil Partnership Act 2004 (CPA 2004), providing them with similar legal rights to married couples.

Originally the CPA 2004 provided for only same sex couples to be able to form civil partnerships. Opposite sex couples can now also form civil partnerships, as a result of amendments to the CPA 2004 made by the Civil Partnership (Opposite-sex Couples) Regulations 2019 (SI 2019/1458) (see Legal update, Civil Partnership (Opposite-sex Couples) Regulations 2019).

Since 13 March 2013, it has been lawful for same-sex couples to marry (section 1, Marriage (Same Sex Couples) Act 2013; see Practice note, Marriage (Same Sex Couples) Act 2013: changes to wills and trust documents: Provisions of MSSCA 2013 that may affect wills and trust documents).