The following signed the letter launching Freedom to Marry:
| Gavin Barwell MP | MP for Croydon Central |
| Lord Black of Brentwood | |
| Alistair Burt MP | MP for North East Bedfordshire |
| Iain Dale | Publisher and LBC Radio Presenter |
| Ruth Davidson MSP | Leader of the Scottish Conservatives |
| Jane Ellison MP | MP for Battersea |
| The Rt Hon The Lord Fowler PC | |
| The Rt Hon Michael Gove MP | MP for Surrey Heath |
| The Rt Hon Nick Herbert MP | MP for Arundel and South Downs |
| Kris Hopkins MP | MP for Keighley |
| Margot James MP | MP for Stourbridge |
| Bernard Jenkin MP | MP for Harwich and North Essex |
| Boris Johnson | Mayor of London |
| The Rt Hon Patrick McLouglin MP | MP for Derbyshire Dales |
| Tim Montgomerie | Editor of ConservativeHome |
| The Baroness Noakes | |
| Matthew Parris | Journalist |
| The Rt Hon Nicholas Soames MP | MP for Mid Sussex |
| Paul Swaddle | President of the Conservative Party National Convention and Party Board Member |
| The Rt Hon Desmond Swayne TD MP | MP for New Forest West |
All support is given in a personal capacity.