49 cities
| City | 2025 Pop. ↓ |
|---|---|
| London | 9,840,740 |
| Liverpool | 928,997 |
| Leicester | 575,352 |
| Leeds | 516,298 |
| Luton | 258,018 |
| Lincoln | 107,434 |
| Londonderry County Borough | 87,153 |
| Lisburn | 77,506 |
| Lowestoft | 70,945 |
| Loughborough | 59,932 |
| Littlehampton | 58,714 |
| Livingston | 56,570 |
| Llanelli | 49,591 |
| Long Eaton | 47,898 |
| Lancaster | 47,162 |
| Leigh | 43,626 |
| Leatherhead | 43,544 |
| Letchworth Garden City | 43,529 |
| Lytham St Annes | 41,327 |
| Leyland | 37,614 |
| Leighton Buzzard | 37,469 |
| Letchworth | 33,955 |
| Lichfield | 32,877 |
| Lower Earley | 32,000 |
| Lofthouse | 23,458 |
| Litherland | 22,971 |
| Leek | 19,903 |
| Lancing | 18,692 |
| Larne | 18,421 |
| Lewes | 17,297 |
| Longfield | 16,808 |
| Lymington | 16,446 |
| Louth | 16,419 |
| Longsight | 16,007 |
| Llandudno | 15,371 |
| Larkhall | 15,020 |
| Llantrisant | 14,422 |
| Llantwit Major | 14,384 |
| Littleborough | 13,807 |
| Linlithgow | 13,320 |
| Limavady | 12,970 |
| Longton | 12,794 |
| Liversedge | 11,656 |
| Lymm | 11,608 |
| Largs | 11,340 |
| Little Lever | 11,329 |
| Leominster | 10,938 |
| Ludlow | 10,515 |
| Little Hulton | 10,216 |