The Gender Recognition Act 2004 is an Act of the Parliament of the United Kingdom that allows people who have gender dysphoria to change their legal gender. It came into effect on 4 April 2005. A Gender Recognition Certificate (GRC) is needed for trans people to change their birth certificate and their sex marker with HMRC. Trans people also need a Gender Recognition Certificate if they want their marriage or civil partnership certificate to reflect their true identity. Only a small percentage of the transgender population in the UK have GRCs on account of the process to get one being laborious, medicalised and intrusive.