| Mrs. Brown's Boys | RTÉ One | sitcom, LGBT-related television series | 3 | 41 |
| MTV's Greatest Hits | — | — | — | — |
| MTV's Most Wanted | — | — | — | — |
| Mud Men | — | — | — | 30 |
| Mud, Sweat and Tears: Premiership Rugby | Amazon Prime Video | — | 1 | 2 |
| Mulberry | BBC One | sitcom | 2 | 13 |
| Multi-Coloured Swap Shop | BBC One | — | 6 | 146 |
| Mum's on Strike | ITV | — | — | — |
| Murdaich | BBC Scotland | children's television | — | — |
| Murder | BBC Two | — | 1 | 4 |
| Murder | British Broadcasting Corporation | — | — | 4 |
| Murder 24/7 | BBC Two | true crime, documentary television program | — | — |
| Murder Before Evensong | Acorn TV, Channel 5 | crime television series | 1 | 6 |
| Murder City | ITV | drama television series | 2 | 10 |
| Murder Files | Channel 5 | — | 1 | 4 |
| Murder in Eden | BBC One | — | 1 | 3 |
| Murder in Mind | BBC One | anthology series, drama television series | 3 | 23 |
| Murder in Provence | — | — | — | — |
| Murder in Suburbia | ITV | drama television series | 2 | 12 |
| Murder in Successville | BBC Three | — | 3 | 18 |
| Murder Investigation Team | ITV | drama television series | 2 | 12 |
| Murder Is Easy | — | mystery fiction, thriller | 1 | 2 |
| Murder Maps | — | docudrama | — | — |
| Murder Most Horrid | BBC Two | anthology series, comedy television series | 4 | 24 |
| Murder Prevention | Channel 5 | drama television series | 1 | 6 |
| Murder Rooms: Mysteries of the Real Sherlock Holmes | BBC Two | detective fiction, drama television series | 1 | 6 |
| Murder Squad | — | documentary television program | 3 | 12 |
| Murder, Mystery, and My Family | — | — | — | — |
| Murder, They Hope | Gold | whodunit, comedy drama, detective fiction | 2 | 6 |
| Murder: First on Scene | CBS Reality | — | — | 10 |
| Murdered by My Boyfriend | BBC Three | — | — | 1 |
| Murderland | ITV1 | drama television series | 1 | 3 |
| Murphy's Law | BBC One | — | 5 | 23 |
| Murphy's Mob | ITV | — | — | 54 |
| Murun Buchstansangur | Channel 4 | — | — | 52 |
| Museum | — | documentary film | — | — |
| Museum of Life | BBC Two | nature documentary | — | 6 |
| Music Room | — | — | 1 | 8 |
| Music Time | — | — | — | — |
| Muslim in Trump's America | — | — | — | — |
| Muslims Like Us | — | — | — | — |
| Mutual Friends | BBC One | comedy drama | 1 | 6 |
| My Almost Famous Family | — | — | 1 | 11 |
| My Brother's Keeper | — | — | — | — |
| My Cousin Rachel | — | — | — | — |
| My Family | BBC One | sitcom | 11 | 120 |
| My Family & Other Turkeys with Nigel Marven | Channel 5 | — | — | — |
| My Family and Other Animals | — | — | — | — |
| My Famous Family | — | — | — | — |
| My Funniest Year | Channel 4 | comedy television series | 1 | 4 |
| My Good Friend | ITV | sitcom | 2 | 14 |
| My Grandparents' War | — | — | — | — |
| My Hero | BBC One | sitcom, science fiction television series | 6 | 51 |
| My High School Musical | — | — | — | — |
| My Honourable Mrs | — | — | — | — |
| My Husband and I | ITV | sitcom | 1 | 7 |
| My Kind of Music | ITV | game show | 5 | 50 |
| My Kind of People | ITV | — | 1 | 10 |
| My Kitchen Rules | — | — | — | 80 |
| My Lady Jane | Amazon Prime Video | — | 1 | 8 |