In a unanimous decision, the Supreme Court has decided that the law preventing opposite sex couples from entering into a civil partnership breaches the European Convention on Human Rights (ECHR). The appellants in this long running case are an opposite sex couple with a conscientious objection to marriage. The crux of this case centred on the issue that when the law was changed in 2013 to allow same-sex couples to marry the older civil partnership rules remained the same. This meant that only two people of the same sex could enter into a civil partnership whilst both same-sex and opposite sex couples could both choose to marry. This created a new inequality affecting opposite sex couples, who for whatever reason, would prefer to enter into a civil partnership rather than marry. Interestingly both the High Court and Court of Appeal had already dismissed the couples claims of discrimination. Although the couple have won their case, it remains to be seen exactly how the government will remedy this inequality. This may take some time and we are likely to see the eventual widening of the civil partnership rules that will allow all unmarried couples to benefit. The civil partnership rules effectively provide for the same tax reliefs as for married couples together with many other legal protections.Cohabiting (same-sex and opposite sex) couples currently have limited legal rights and they should carefully consider their position especially when purchasing property together or building a family.