| Ultimate Guinness World Records | — | — | — | — |
| Ultraviolet | Channel 4 | science fiction television series, horror television series | 1 | 6 |
| Unacceptable | TLC | — | — | — |
| Unanimous | Channel 4 | — | — | 8 |
| Unbreakable | Channel 5 | — | 1 | 8 |
| Unchosen | Netflix | — | 1 | 6 |
| Uncle | BBC Three, British Broadcasting Corporation | sitcom | 3 | 12 |
| Uncle Dad | ITV | — | 1 | 7 |
| Uncle Jack | BBC One | — | 4 | 24 |
| Uncle Max | — | — | 2 | 26 |
| Under and Over | — | sitcom | — | — |
| Under Offer | — | game show | 4 | 51 |
| Under the Hammer | — | — | — | — |
| Under the Moon | Channel 4 | — | — | — |
| Undercover | BBC One | — | 1 | 6 |
| Undercover | — | — | 1 | 6 |
| Undercover Dads! | — | children's television series | — | — |
| Undercover Heart | — | — | — | 6 |
| Undercover Lovers | — | reality television | — | 15 |
| Undercover Mosque: The Return | — | documentary television program | — | — |
| Undercover Princesses | BBC Three | docu-soap | 1 | 4 |
| Underground Ernie | CBeebies | — | — | 26 |
| Undermind | ITV | science fiction television series, drama television series | 1 | 11 |
| Uned 5 | S4C | children's television series | — | 1,159 |
| Unfinished Business | — | — | — | — |
| Unforgiven | ITV1 | drama television series | 1 | 3 |
| Unforgotten on Masterpiece | ITV | crime television series, drama television series | 5 | 30 |
| Union Castle | — | — | — | — |
| United | BBC Two | association football film | 1 | 6 |
| United! | — | — | 1 | 147 |
| University Challenge | ITV, BBC Two | quiz show | 53 | — |
| University Challenge 2016–17 | — | — | — | — |
| Unnatural Acts | Q1114052 | sketch comedy | 1 | 6 |
| Unnatural Causes | — | — | — | 7 |
| Unnatural Histories | BBC Four | nature documentary | 1 | 3 |
| Unnovations | Play UK | comedy television series | 1 | 10 |
| Unprecedented | BBC Four | — | 1 | 5 |
| Unreported World | Channel 4 | documentary film, documentary television program | — | — |
| Unsolved: The Boy Who Disappeared | — | — | 1 | 8 |
| Unspun with Matt Forde | — | — | 2 | 6 |
| Untamed China with Nigel Marven | Animal Planet | nature documentary | — | 6 |
| Unwind with ITV | — | — | — | — |
| Unzipped | BBC Three | comedy television series | 2 | 14 |
| Up in Town | BBC Two | — | — | 6 |
| Up Late with Rylan | Channel 5 | — | — | 16 |
| Up Pompeii! | BBC One | sitcom | — | — |
| Up Sunday | BBC Two | comedy television series | — | — |
| Up the Elephant and Round the Castle | ITV | sitcom | 3 | 22 |
| Up the Women | BBC Four | sitcom | 2 | 9 |
| UP2U | — | children's television series | — | — |
| Upstairs Downstairs | BBC One | drama television series, period drama film | 2 | 9 |
| Upstairs, Downstairs | ITV | drama television series | 5 | 68 |
| Upstart Crow | BBC Two | sitcom | 1 | 6 |
| Urban Gothic | Channel 5 | anthology series | 2 | 22 |
| Urban Myth Chillers | — | — | 1 | 25 |
| Urban Myths | — | — | 1 | 6 |
| Us Girls | BBC One | sitcom | — | 12 |
| Utopia | Channel 4 | thriller television series, drama television series | 2 | 12 |
| UTV Live | UTV | — | — | — |
| V Graham Norton | Channel 4 | comedy television series | 5 | 65 |