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 | |
| Municipal Reform League | Pressure group |