| Lighthouse Electrical & Plumbing Ltd | Construction | 2026 |
| Lighthouse Lettings and Investments Limited | Real estate | 2023 |
| Lights, Camera, Doris! Ltd | Information & communication | 2025 |
| Lightwave Consulting Ltd | Professional & scientific | 2019 |
| Lightwave Networks Ltd | Other services | 2025 |
| Lightweight Integration Limited | Professional & scientific | 2013 |
| Like Sherbet Ltd | Professional & scientific | 2011 |
| Likelihood Studio Ltd | Information & communication | 2022 |
| Likelyadvice Limited | Professional & scientific | 1999 |
| Lilly DRY Cleaners Ltd | Other services | 2025 |
| Lillyandsid Ltd | Wholesale & retail | 2009 |
| Lily & ROO Ltd | Manufacturing | 2018 |
| Lily Cleaning Services Limited | Administrative & support | 2021 |
| Lime Green IT Limited | Information & communication | 2013 |
| Lime Tree Management Limited | Hospitality | 1981 |
| Limehouse Recordings Ltd. | Information & communication | 2006 |
| Limelight Ventures Ltd | Wholesale & retail | 2021 |
| Limentra Limited | Professional & scientific | 2011 |
| Limeswood Properties Limited | Real estate | 2022 |
| Limina Fitness Limited | Manufacturing | 2022 |
| Limitless Plumbing Ltd | Construction | 2015 |
| Limitless Technologies Limited | Information & communication | 2019 |
| Limrah Traders Limited | Wholesale & retail | 2024 |
| Linanben Limited | Financial services | 2024 |
| Linares Process Engineering Limited | Professional & scientific | 2011 |
| Lincoln Court Management (Berkhamsted) Limited | Households | 1974 |
| Lincoln Exley Designs Limited | Professional & scientific | 1996 |
| Lindfield Gardens Management Company Limited | Households | 1997 |
| Lindsay Evans Careers Guidance Services Limited | Education | 2012 |
| Lindsey Investments Ltd | Construction | 2016 |
| Line of Site Ltd | Construction | 2016 |
| Linear AI Limited | Information & communication | 2023 |
| Linga-Yoni Limited | Wholesale & retail | 2013 |
| Lingmoor Finance Limited | Financial services | 2026 |
| Link Global Management Ltd | Professional & scientific | 2016 |
| Link Tech Group Ltd | Administrative & support | 2024 |
| Link-Estate Agents Ltd | Real estate | 2018 |
| Link-Estates Limited | Real estate | 2010 |
| LINK77 Homes Ltd | Real estate | 2021 |
| Linklater Consultancy Ltd | Wholesale & retail | 2024 |
| Links Furniture Limited | Wholesale & retail | 2017 |
| Linktogrow Ltd | Health & social care | 2023 |
| Linkview Services Ltd | Administrative & support | 2025 |
| Linqard Ltd | Professional & scientific | 2023 |
| Linxbeyond Ltd | Professional & scientific | 2024 |
| Lion Alliance European Ltd | Wholesale & retail | 2018 |
| Lion Plumbing Ltd | Construction | 2011 |
| Lionel House (Palmerston Road) Property Management Companylimited | Real estate | 1964 |
| Liquiditas Limited | Construction | 2006 |
| Liquidity Trading Central Ltd | Financial services | 2025 |
| Lisa Cook Property Services Ltd | Real estate | 2023 |
| Lisa KAY Limited | Wholesale & retail | 2009 |
| Lisha Gorasiya Designs Ltd | Professional & scientific | 2025 |
| Lisistar Corporation Ltd | Wholesale & retail | 2021 |
| Liston and Company Limited | Administrative & support | 1979 |
| Liston Ferry Partnership Ltd | Professional & scientific | 2016 |
| Litelia Ltd | Information & communication | 2016 |
| Little & Little Ltd | Extraterritorial | 2019 |
| Little Alpine Ltd | Hospitality | 2018 |
| Little Alpine Properties Ltd | Real estate | 2023 |
| Little Angel's Nursery and Preschool Ltd | Education | 2025 |
| Little Blossom Nursery School Ltd | Health & social care | 2022 |
| Little Brook (Bushey) Management Limited | Households | 1994 |
| Little Elebo Ltd | Wholesale & retail | 2025 |
| Little Hands Adventure Club Limited | Health & social care | 2017 |
| Little Jams Limited | Wholesale & retail | 1964 |
| Little Learners Montessori Ltd | Education | 2012 |
| Little Miss Plumbing and Heating Limited | Construction | 2024 |
| Little Miss Properties Limited | Real estate | 2025 |
| Little Oxhey Limited | Real estate | 2023 |
| Little Rebel Management Ltd | Extraterritorial | 2013 |
| Little Runners Ltd | Health & social care | 2015 |
| Little Stars Norfolk Ltd | Health & social care | 2024 |
| Little Steps Coaching Ltd | Other services | 2025 |
| Little Stratford Limited | Real estate | 2018 |
| Littlebox Accounting Solutions Limited | Professional & scientific | 2013 |
| Live and LET Live (Hitchin) Ltd | Hospitality | 2020 |
| Live Himalayan Ltd | Wholesale & retail | 2025 |
| Live NOW App Limited | Information & communication | 2024 |
| Lively Services Ltd | Information & communication | 2020 |
| Livewire Consultancy Limited | Wholesale & retail | 2018 |
| Livewire Software Systems Ltd | Information & communication | 2015 |
| Livi Body Sculpt Ltd | Other services | 2019 |
| Living Haus Limited | Construction | 2020 |
| Living in Saudi Ltd | Real estate | 2026 |
| Living Word Missionary Church - UK | Other services | 2009 |
| Livingstondrive Limited | Education | 2022 |
| Liya Optical Ltd | Other services | 2024 |
| LIZ Hall Hotel & Travel Consulting Ltd | Professional & scientific | 2018 |
| Lizard DEN Ltd | Manufacturing | 2020 |
| LJ Consulting Services Limited | Professional & scientific | 2015 |
| LJL Holdings Ltd | Real estate | 2018 |
| LK Fencing Ltd | Construction | 2021 |
| LK Prime Distributors Limited | Wholesale & retail | 2026 |
| LL Consultancy Ltd | Professional & scientific | 2018 |
| Ll&Zg Limited | Wholesale & retail | 2024 |
| Llab Limited | Professional & scientific | 2016 |
| LLJ Properties Ltd | Real estate | 2023 |
| LLV Financial Limited | Professional & scientific | 2019 |
| LM LAI Medical Services Ltd | Wholesale & retail | 2020 |