| Law Air Limited | Administrative & support | 2023 |
| Lawrence Dean Recruitment Ltd | Administrative & support | 2010 |
| Lawtey Design Limited | Professional & scientific | 2018 |
| Layoutindex UK Ltd | Information & communication | 2022 |
| Lazarim Ltd | Manufacturing | 2019 |
| Lazerbuilt Limited | Manufacturing | 1981 |
| LBK Staffing Ltd | Health & social care | 2025 |
| LCA Plant Services Limited | Manufacturing | 2024 |
| Lcajobs Ltd | Professional & scientific | 2003 |
| Lcgk Lettings Limited | Real estate | 2017 |
| LCP Motors Limited | Transport & logistics | 2018 |
| Lcretail Ltd | Wholesale & retail | 2026 |
| LDA Tech Ltd | Administrative & support | 2017 |
| LE Roux Beauty Ltd | Other services | 2021 |
| Lead Care Services Limited | Health & social care | 2016 |
| Lead Care Support Services Ltd | Health & social care | 2020 |
| Leader Productions Ltd | Information & communication | 2023 |
| Leadership Mastery Limited | Other services | 2016 |
| Leading Edge Cutter Makers Limited | Administrative & support | 2014 |
| Leagrove Limited | Real estate | 2009 |
| Leahz Limited | Wholesale & retail | 2025 |
| Leanerlife Challenge Limited | Education | 2018 |
| Leanerlife Fitness Limited | Other services | 2016 |
| Leanerlife Hyrox Limited | Arts & recreation | 2026 |
| Leanerlife Limited | Education | 2020 |
| Leanerlife Training Limited | Education | 2018 |
| Leanerlife VIP Limited | Arts & recreation | 2026 |
| Leaps Dance Academy Ltd | Arts & recreation | 2023 |
| Leaps Dancewear Ltd | Wholesale & retail | 2024 |
| Learn to Dream Group Limited | Professional & scientific | 2004 |
| LEARN2PROFIT Limited | Professional & scientific | 2009 |
| Learning Zone Partnership Limited | Health & social care | 2019 |
| Leatherfield Developments Limited | Real estate | 2016 |
| Leavened Ltd | Manufacturing | 2020 |
| Lecommerce Limited | Wholesale & retail | 2023 |
| Ledgewoods Electrical Services Limited | Construction | 2017 |
| Ledman Ltd | Wholesale & retail | 2022 |
| LEE Smith Magic Limited | Administrative & support | 2018 |
| Leelac Limited | Wholesale & retail | 2015 |
| Lees-Milne Investments Limited | Financial services | 2014 |
| Legacy Carpentry Ltd | Manufacturing | 2020 |
| Legacy Developments Spcwes Limited | Construction | 2025 |
| Legal Link Couriers & Removals Ltd | Transport & logistics | 2025 |
| Legal Zone Ltd | Extraterritorial | 2023 |
| Leigh Howard Associates Limited | Other services | 2018 |
| Leisure Services (Gants Hill) Limited | Arts & recreation | 2023 |
| Lela Healthcare Ltd | Health & social care | 2023 |
| Lemon Homes Ltd | Real estate | 2021 |
| Lemon Trees on Mercury Ltd | Hospitality | 2020 |
| Lemsford Building Ltd | Construction | 2025 |
| Lenani Care Services Ltd | Health & social care | 2025 |
| Lennie's Lens Photography Ltd | Professional & scientific | 2025 |
| Lenny's Fresh Fish Limited | Wholesale & retail | 2015 |
| Leon JA Construction Limited | Construction | 2024 |
| Leon JA Limited | Other services | 2023 |
| Leon JA Properties Limited | Real estate | 2023 |
| Leotel Software Systems Limited | Information & communication | 2002 |
| LER Claims Contractors Limited | Construction | 2018 |
| Leroy Anesu Limited | Health & social care | 2011 |
| LES Jackson Services Ltd | Transport & logistics | 2023 |
| Lescarbon Ltd | Construction | 2023 |
| Leshi Newsbox Limited | Wholesale & retail | 2023 |
| LET the World Know WHO YOU ARE Ltd | Administrative & support | 2025 |
| Let's Protest.Co.Uk Ltd | Other services | 2023 |
| Letchworth Carpet Centre Fitting Ltd | Construction | 2026 |
| Letchworth Rehabilitation & Physiotherapy Centre Ltd | Other services | 2019 |
| Lets Landlord Ltd | Households | 2020 |
| Let’S Sell in the South East Limited | Real estate | 2019 |
| Level One Records Ltd | Information & communication | 2018 |
| Lever Post and Production Ltd | Professional & scientific | 2018 |
| Leverage Properties Limited | Administrative & support | 2016 |
| Lewsett & Sons Ltd | Wholesale & retail | 2021 |
| Lexal Ltd | Health & social care | 2020 |
| Lezzet Pizza & Kebab Ltd | Hospitality | 2025 |
| LF Premier Meats Ltd | Wholesale & retail | 2021 |
| LFB Consultants Ltd | Health & social care | 2020 |
| Lflux Chauffeurs Limited | Transport & logistics | 2026 |
| LG & Mabel Trading Limited | Other services | 2024 |
| LG Johnson Limited | Professional & scientific | 2011 |
| LGP Solutions Limited | Information & communication | 2022 |
| Lgpn Ltd | Health & social care | 2025 |
| LH REC Consulting Ltd | Administrative & support | 2017 |
| Lhouette Studios Ltd | Arts & recreation | 2017 |
| Liam Lockspeiser Ltd | Information & communication | 2020 |
| Lianapa Ltd | Health & social care | 2018 |
| Libero Property Group Limited | Real estate | 2015 |
| Lidia's Little Happy Learners Ltd | Health & social care | 2025 |
| Liern Healthcare Ltd | Health & social care | 2016 |
| Lifecast Studio Limited | Arts & recreation | 2025 |
| Lifeethics Ltd | Health & social care | 2023 |
| Light City Ltd | Wholesale & retail | 2018 |
| Light Space Architecture Limited | Professional & scientific | 2015 |
| Lightworks Electrics Limited | Construction | 2023 |
| Liin Couture Limited | Wholesale & retail | 2025 |
| Lillianhomes Properties Limited | Real estate | 2025 |
| Lily Healthcare & Supported Living Limited | Health & social care | 2022 |
| LIM Development Limited | Real estate | 2024 |
| Lime Close 1960 Limited | Extraterritorial | 2015 |
| Limehouse Lock Limited | Real estate | 2014 |
| Limitededition Comix Limited | Administrative & support | 2008 |