| LDV Sitaram Limited | Hospitality | 2024 |
| LE Cercle Ltd | Wholesale & retail | 2013 |
| Leach Property Services Limited | Households | 2019 |
| Leafcutter Design Ltd | Wholesale & retail | 1999 |
| Leddra Perry & Co Limited | Professional & scientific | 2002 |
| Leisure & Co Hotel (Peterborough) Ltd | Hospitality | 2026 |
| Leisure & Co Hotel Ltd | Hospitality | 2026 |
| Lepik & Gray Ltd | Construction | 2006 |
| Letterbox Property Developments Limited | Construction | 2018 |
| LEVEL1 Consultancy and Training Limited | Public administration | 2011 |
| Lexie Enterprises 2015 Limited | Extraterritorial | 2015 |
| Lgsc Life Ltd | Administrative & support | 2023 |
| LH Agro (UK) Limited | Agriculture & fishing | 1987 |
| Lightstone Systems Limited | Information & communication | 2009 |
| Lila Transport Services Ltd | Transport & logistics | 2019 |
| Lime Precision Ltd | Manufacturing | 2025 |
| Limeflower Bookkeeping Ltd | Professional & scientific | 2022 |
| Lina Medical Services Ltd | Health & social care | 2026 |
| Lina Service Limited | Other services | 2011 |
| Lincs Classics Limited | Wholesale & retail | 1996 |
| Lincs Coast Leisure Ltd | Hospitality | 2019 |
| Link One Consultancy Limited | Professional & scientific | 2015 |
| Lisa TAN Pharma Consulting Limited | Professional & scientific | 2010 |
| Little Acorn Day Nurseries Ltd | Health & social care | 2008 |
| Little Acorns Hampton Day Nursery and Montessori School Limited | Health & social care | 2024 |
| Little Fishes Swim School Limited | Education | 2016 |
| Little Lolita Croft Ltd | Real estate | 2019 |
| Little Mermaid ST Ives Ltd | Transport & logistics | 2025 |
| Little Palais Limited | Hospitality | 2022 |
| Live Wires Electrical Contractors Ltd | Construction | 2008 |
| Livify Estates Ltd | Real estate | 2025 |
| Living Active Limited | Extraterritorial | 2018 |
| Living Sport Cambridgeshire and Peterborough Sports Partnership Limited | Arts & recreation | 2006 |
| Lizardfish TV Ltd | Information & communication | 2011 |
| LLL Cambridge Ltd | Hospitality | 2022 |
| LM Thompson Ltd | Real estate | 2026 |
| Lmcgh Limited | Professional & scientific | 2000 |
| London Marine Ltd | Administrative & support | 2004 |
| Look Again Textiles Ltd | Wholesale & retail | 2025 |
| Louise Austin Travel Ltd | Administrative & support | 2025 |
| Loveday Engineering Limited | Manufacturing | 2002 |
| LS Holidays Ltd | Hospitality | 2022 |
| LSJ Asbestos Services Ltd | Water & waste | 2021 |
| LSM Wheel Restoration Ltd | Wholesale & retail | 2026 |
| Luca's Doggy Daycare Ltd | Other services | 2022 |
| Luca's Grooming HUT Ltd | Other services | 2025 |
| Lucks Lane Investments Limited | Real estate | 2010 |
| Luisa Baldini Ltd | Professional & scientific | 2021 |
| Lukasz Dabrowski Peja Ltd | Wholesale & retail | 2017 |
| Lukation Ltd | Information & communication | 2024 |
| Lune Edge Trade Group Limited | Construction | 2025 |
| Lush Green Investments Ltd | Real estate | 2020 |
| Lutosa UK Limited | Wholesale & retail | 1979 |
| Luxe Bars Limited | Hospitality | 2025 |
| Luxury Lemon Ltd | Professional & scientific | 2015 |
| Luxury Nails ST Ives Ltd | Other services | 2026 |
| Lynch Legacy Ventures Ltd | Administrative & support | 2025 |
| M & a One Million One Limited | Transport & logistics | 2019 |
| M & B Green Limited | Real estate | 2013 |
| M & K Corporation Limited | Financial services | 2020 |
| M Build Building Contractors Limited | Construction | 2013 |
| M D Couriers Limited | Transport & logistics | 2000 |
| M Peacey Construction Ltd | Construction | 2026 |
| M Vince Nail Spa Ltd | Other services | 2023 |
| M.R. Smith Brickwork Ltd. | Construction | 2008 |
| M3ST Holdings Limited | Financial services | 2017 |
| M3ST IPX Limited | Information & communication | 2020 |
| M3ST Limited | Information & communication | 2012 |
| Macey & Co Holdings Ltd | Financial services | 2026 |
| Machine-Dependent Ltd | Manufacturing | 2024 |
| Macwell Developments Limited | Manufacturing | 1987 |
| MAD Retail Limited | Wholesale & retail | 2022 |
| Madhouse INK Limited | Other services | 2020 |
| Madvie Heating & Plumbing Services Ltd | Construction | 2008 |
| Magdellan Management Services Limited | Financial services | 2016 |
| Magstar Limited | Professional & scientific | 2002 |
| Maid by the Sea Ltd | Administrative & support | 2026 |
| Maintenance ST Ives 247 Ltd | Other services | 2018 |
| Major Smiles Limited | Health & social care | 2013 |
| Makki Limited | Extraterritorial | 2012 |
| Malcolm Thomas Ltd | Real estate | 2003 |
| Malcolms Residential Ltd | Real estate | 2019 |
| Malsen UK Limited | Professional & scientific | 2025 |
| Mama Reyna Limited | Manufacturing | 2014 |
| Managed Printing Services Limited | Manufacturing | 2008 |
| Manak Optical Services Ltd | Health & social care | 2006 |
| Manfuls Ltd | Professional & scientific | 2020 |
| Manny Tripp Badminton Coaching Limited | Arts & recreation | 2024 |
| Manse Consulting Limited | Professional & scientific | 2024 |
| MAP Colnbrook Limited | Construction | 2025 |
| Mapgro Limited | Financial services | 2019 |
| Maple Leaf Construction Limited | Construction | 2019 |
| Maple Tree Property Ltd | Construction | 2024 |
| Maps SPV Ltd | Real estate | 2021 |
| Marazion Solutions Ltd | Professional & scientific | 2023 |
| Marbled Ltd | Construction | 2024 |
| Margetts Ashford Limited | Professional & scientific | 2016 |
| Mark Flack Limited | Construction | 2005 |
| Mark Taylor Marketing Limited | Professional & scientific | 2015 |
| Marksman Motorsport Limited | Wholesale & retail | 2024 |