Political organisations
M
| Name | Type | Notes |
|---|---|---|
| Magistrates' Association | Miscellaneous | |
| Manchester Norman Angell League | Miscellaneous | |
| Manchester Unity of Oddfellows | Miscellaneous | |
| Market Research Society | Trade Group | |
| Master Sadlers Co | Miscellaneous | |
| Mechanics Institute | Miscellaneous | |
| Medical campaign against nuclear weapons | Pressure Group | |
| Medical Research Council | Miscellaneous | |
| Menswear Association of great Britain | Miscellaneous | |
| Methodist New Connection | Religious | |
| Methodist Union | Religious | |
| Mewadd Deg | Miscellaneous | |
| Middle Classes Union | Cultural | |
| MIND | Pressure Group | Schizophrenia Association |
| Miners' International Federation | International Body | |
| Mining Association of GB | Miscellaneous | |
| Monday Club | Party Group | |
| Monday Club | Party Group | |
| Monday Club | Party Group | |
| Monday Club | Party Group |