| Lettify Limited | Real estate | 2025 |
| Letting Property Investment Ltd | Real estate | 2025 |
| Leucid BIO Ltd | Professional & scientific | 2014 |
| LEV Developments Ltd | Construction | 2024 |
| Levancy Limited | Extraterritorial | 2026 |
| Level UP Gym Ltd | Arts & recreation | 2023 |
| Levelheaded Limited | Professional & scientific | 2000 |
| Levelheaded Trustees Limited | Administrative & support | 2018 |
| Leves Co., Limited | Extraterritorial | 2024 |
| Levidian Nanosystems Limited | Professional & scientific | 2012 |
| Levin Sources Limited | Administrative & support | 2010 |
| Levy Hill Group Limited | Extraterritorial | 1998 |
| Levy Hill Laboratories Limited | Extraterritorial | 1994 |
| Lewandowski (UK) Ltd | Construction | 2014 |
| Lewin Smith & Company Limited | Real estate | 1956 |
| Lewin Smith Holdings Limited | Financial services | 2022 |
| Lewis Gibson Limited | Real estate | 2000 |
| Lewis Tree Surgery Ltd | Agriculture & fishing | 2016 |
| LEX EX Machina Limited | Professional & scientific | 2017 |
| Lexin Industrial Co., Limited | Wholesale & retail | 2023 |
| LEY Construction Ltd | Construction | 2008 |
| Leydenbless Limited | Information & communication | 2010 |
| Leys Avenue (Cambridge) Management Company Limited | Households | 2021 |
| Leys Enterprises (Cambridge) Limited | Wholesale & retail | 1986 |
| Lezak Group Ltd | Construction | 2025 |
| LFF Trading Ltd | Wholesale & retail | 2016 |
| LFM Software Limited | Information & communication | 2001 |
| Lfpcsa C.I.C. | Administrative & support | 2025 |
| LGM Industrial Co., Ltd | Manufacturing | 2019 |
| LGV5 Ltd | Manufacturing | 2018 |
| LI Composites Ltd | Manufacturing | 2018 |
| Li-Cor Biosciences UK Limited | Wholesale & retail | 2001 |
| Lia-Recruitment&Transport Ltd | Transport & logistics | 2023 |
| Liam Masterson Limited | Health & social care | 2023 |
| Lianchao Future Technology Co., Ltd | Professional & scientific | 2010 |
| Liberatore Composite Ltd | Manufacturing | 2022 |
| Liberomassage Cambridge Ltd | Health & social care | 2022 |
| Liberty Communications Ltd | Professional & scientific | 2024 |
| Liberum Fortuna Ltd | Manufacturing | 2018 |
| Libra Roofing & Scaffolding Ltd | Construction | 2026 |
| Libra Security Limited | Administrative & support | 2017 |
| LICA-1997AVIATION Ltd | Manufacturing | 2025 |
| Lico Marine Engineering Co., Ltd. | Wholesale & retail | 2025 |
| Lidercare Technology Co., Ltd | Manufacturing | 2024 |
| Lidya Tech Limited | Information & communication | 2020 |
| Life After Professional Sport Ltd | Administrative & support | 2016 |
| Life Biomedical Limited | Wholesale & retail | 2012 |
| Life Communities Ltd | Real estate | 2023 |
| Life Innovation Group Holding Ltd | Health & social care | 2024 |
| Life Squared Management Company Limited | Households | 2013 |
| Lifeline Construction Ltd | Construction | 2019 |
| Lifeline Property Ltd | Professional & scientific | 1990 |
| Lifesaver Cambridge Limited | Construction | 2013 |
| Lifespan Solutions AG Ltd | Professional & scientific | 2026 |
| Lifestyle NI Management Limited | Real estate | 2015 |
| Lifetime (Holdings) Limited | Financial services | 1995 |
| Lifetime Films Limited | Information & communication | 1993 |
| Lifetime Ltd | Professional & scientific | 2026 |
| Lifetime Productions International Limited | Information & communication | 1985 |
| Lifetime Vision Limited | Information & communication | 1990 |
| Light Blue Clinic Ltd | Health & social care | 2021 |
| Light Blue Fibre Limited | Information & communication | 2019 |
| Light Blue Holdings Ltd | Administrative & support | 2018 |
| Light Blue Properties Ltd | Real estate | 2023 |
| Light Blue Software Limited | Information & communication | 2008 |
| Light Earth Designs LLP | | 2012 |
| Light Squares Ltd | Information & communication | 2025 |
| Light UP Love Limited | Administrative & support | 2017 |
| Light Year Tech Co., Ltd | Wholesale & retail | 2023 |
| Lightcast Discovery Ltd | Professional & scientific | 2019 |
| Lighten Enterprise Co., Ltd | Manufacturing | 2020 |
| Lighthouse Accountancy Ltd. | Professional & scientific | 2006 |
| Lightning Aviation Ltd | Manufacturing | 2018 |
| Lightning Lighting Ltd | Wholesale & retail | 2015 |
| Lightning Tree Advanced Materials Ltd | Professional & scientific | 2025 |
| Ligmach Trading Co., Ltd | Wholesale & retail | 2022 |
| Lignumarium Ltd | Professional & scientific | 2025 |
| Ligo Design Ltd | Financial services | 2024 |
| Lijie Holdings Limited | Wholesale & retail | 2026 |
| Lijing Household Products Co., Ltd. | Manufacturing | 2024 |
| Like IT Beauty Ltd | Other services | 2025 |
| Like IT Ltd | Other services | 2025 |
| Likeko Ltd | Wholesale & retail | 2025 |
| Lilac Property Lets Ltd | Real estate | 2023 |
| Lilalux Ltd | Wholesale & retail | 2024 |
| Lildex Limited | Financial services | 2021 |
| Lildex Property Limited | Real estate | 2021 |
| Lilley of Sawston Ltd | Administrative & support | 2021 |
| Lillys Lettings Limited | Real estate | 2008 |
| Lily & Jack's Ltd | Other services | 2014 |
| Lily Linford-Hurst Limited | Professional & scientific | 2024 |
| Lily Wolf Limited | Wholesale & retail | 2025 |
| Lilyvee Consulting Ltd | Professional & scientific | 2025 |
| LIM & LU Property Limited | Real estate | 2016 |
| Limb Reconstructions Ltd | Manufacturing | 2018 |
| Lime Innovations Limited | Professional & scientific | 2021 |
| Lime Tree FS (Cambridge) Ltd | Financial services | 2021 |
| Limeai Law Limited | Information & communication | 2026 |
| Limerick (Balham) Residents Company Limited | Households | 2013 |
| Limetree Craft Limited | Wholesale & retail | 2021 |