| The Last Detective | ITV | drama television series, crime television series | 4 | 17 |
| The Last Enemy | BBC One | drama fiction | 1 | 5 |
| The Last Kingdom | BBC Two | historical drama | 6 | 46 |
| The Last Leg | Channel 4 | late-night talk show | 10 | 157 |
| The Last Man Out | — | — | — | — |
| The Last Millionaire | — | reality television | 1 | 6 |
| The Last of the Baskets | ITV | sitcom | 2 | 13 |
| The Last Panthers | Sky Atlantic | crime television series | 1 | 6 |
| The Last Place on Earth | ITV Central | drama television series | 1 | 7 |
| The Last Post | BBC One | drama television series | 1 | 6 |
| The Last Train | ITV | science fiction television series, post-apocalyptic television series, drama television series | 1 | 6 |
| The Last Weekend | — | drama television series | 1 | 3 |
| The Late Edition | BBC Four | — | — | — |
| The Late Show | BBC Two | — | — | — |
| The Late, Late Breakfast Show | BBC One | game show | 5 | 77 |
| The Laughter Show | BBC One | comedy television program | 8 | 51 |
| The Lavender List | — | — | — | — |
| The Law of the Playground | Channel 4 | — | 2 | 13 |
| The League of Gentlemen | BBC Two | comedy television series, LGBT-related television series | 3 | 19 |
| The Legend of Dick and Dom | BBC Children's and Education | sitcom | 3 | 33 |
| The Legend of King Arthur | BBC One | — | 1 | 8 |
| The Legend of Robin Hood | BBC One | drama television series | — | 6 |
| The Legend of the Lost Keys | — | — | 1 | 10 |
| The Lenny Henry Show | — | comedy television series | 7 | 48 |
| The Les Dawson Show | BBC One | variety show | — | 34 |
| The Letter for the King | Netflix | fantasy television series, drama television series, adventure television series, family television series | 1 | 6 |
| The Level | ITV | — | 1 | 6 |
| The Liars | ITV | — | 1 | 13 |
| The Life and Times of David Lloyd George | BBC One | biographical film, drama television series, historical television series | — | 9 |
| The Life and Times of Vivienne Vyle | BBC Two | sitcom | 1 | 6 |
| The Life of Birds | BBC One | nature documentary, documentary film | — | 10 |
| The Life of Mammals | BBC One | nature documentary, documentary film | — | 10 |
| The Life of Muhammad | BBC Two | documentary film, documentary television program | 1 | 3 |
| The Likeaballs | — | — | — | — |
| The Likely Lads | British Broadcasting Corporation | sitcom | 3 | 20 |
| The Lingo Show | — | children's television series | — | 31 |
| The Link | BBC One | game show | 2 | 65 |
| The Lion, the Witch and the Wardrobe | BBC One | fantasy television series | — | 6 |
| The Lion, the Witch and the Wardrobe | ITV | fantasy television series | 1 | 10 |
| The Listeners | BBC One | psychological thriller | 1 | 4 |
| The Little and Large Show | — | comedy television series | 11 | 76 |
| The Little Drummer Girl | BBC One | drama television series, espionage television series | 1 | 6 |
| The Little Green Man | ITV | — | 1 | 13 |
| The Little World of Don Camillo | British Broadcasting Corporation | comedy | 1 | 12 |
| The Liver Birds | BBC One | sitcom | 10 | 86 |
| The Living and the Dead | BBC One, BBC America | drama television series, thriller television series, horror television series | 1 | 6 |
| The Living Planet | BBC One | nature documentary | — | 12 |
| The Living Soap | — | documentary film, reality television | — | — |
| The Lock Up | BBC Three | documentary film, reality television | 2 | 10 |
| The Lodge | Disney Channel, Disney Channel | drama television series | 2 | 25 |
| The London Palladium Show | — | — | — | — |
| The Long Call | ITV | — | — | 4 |
| The Long Search | — | documentary film, documentary television program | 1 | 13 |
| The Long Shadow | — | — | — | — |
| The Losers | ITV | sitcom | 1 | 6 |
| The Lost Centuries | — | — | — | — |
| The Lost Evidence | — | documentary film | — | — |
| The Lost World of Communism | — | documentary television program | — | 3 |
| The Lost World of Mitchell & Kenyon | BBC One | documentary film | — | 3 |
| The Love Machine | — | game show | 2 | — |