Couples who have formed a Civil Partnership have the option to convert this to a Marriage. Fees The fee for a conversion is currently £45. A marriage certificate may be purchased after the conversion has been completed. Certificates are £11 per copy, and will show the date of marriage as the original Civil Partnership date. The Registrar can talk you through the process when you call to book. Alternatively, you can email email@example.com for more information. Documents needed You will be required to produce original documents that show your details including: names date of birth addresses your existing Civil Partnership certificate. Conversion process The conversion process is administrative and no guests or witnesses are required, as there is no ceremony involved.