| Littlen Pubs Limited | Hospitality | 2025 |
| Live News Limited | Wholesale & retail | 2017 |
| Livingcreation Ltd | Construction | 2026 |
| LJN Jewellery Limited | Wholesale & retail | 2012 |
| LJP Domestic Services Ltd | Administrative & support | 2025 |
| Lj’S Auto Solutions Ltd | Wholesale & retail | 2026 |
| LLM Rentals Ltd | Real estate | 2023 |
| LLT Thompson Ltd | Hospitality | 2025 |
| LMB Groundworks Ltd | Construction | 2021 |
| LMD Rentals Ltd | Real estate | 2025 |
| Lmech Ltd | Professional & scientific | 2022 |
| LMG East Anglia Ltd | Financial services | 2013 |
| LNA Eaton Limited | Construction | 2019 |
| Loan Machine Limited | Financial services | 2005 |
| Lobec Fabrication Services Limited | Administrative & support | 2017 |
| Local China Ltd | Hospitality | 2026 |
| Local Market Expert Ltd | Extraterritorial | 2022 |
| Localhse Ltd | Professional & scientific | 2024 |
| Lockwood Plumbing Heating and GAS Services Limited | Construction | 2005 |
| Locum Management Ltd | Administrative & support | 2016 |
| Locum-Sphere Ltd | Administrative & support | 2018 |
| Logic Projects Ltd | Transport & logistics | 2025 |
| Logics Void Ltd | Wholesale & retail | 2024 |
| Lojer Products Limited | Professional & scientific | 1987 |
| Loler Rigging & Lifting Ltd | Construction | 2026 |
| Lonely Llama CIC | Professional & scientific | 2025 |
| Longview Caravan and Camping Site Limited | Hospitality | 2014 |
| Looksubmit Limited | Real estate | 1992 |
| Lord Choo Choo Limited | Arts & recreation | 2005 |
| Losgaintir Ltd | Extraterritorial | 2024 |
| Louise RN Aesthetics Limited | Health & social care | 2023 |
| Love ABA Ltd | Education | 2016 |
| Love Bespoke Limited | Manufacturing | 2019 |
| Love Your Teeth Limited | Health & social care | 2016 |
| Loved Ones Home Care Ltd | Health & social care | 2022 |
| Loveday Entertainment Ltd | Hospitality | 2019 |
| Lovewell Blake Accountancy Services Limited | Professional & scientific | 1988 |
| Lovewell Blake Employment Services Limited | Administrative & support | 2020 |
| Lovewell Blake LLP | | 2010 |
| Lovewell Blake Services Limited | Information & communication | 1976 |
| Lowestoft Boxing Academy Limited | Arts & recreation | 2025 |
| Lowestoft Funeral Directors Limited | Extraterritorial | 2017 |
| Lowestoft Tile Company Limited | Wholesale & retail | 1984 |
| Lowland Property Group Ltd | Real estate | 2025 |
| LP Dental Wellness Limited | Health & social care | 2025 |
| LP Energy Services Ltd | Extraterritorial | 2025 |
| LP Marine Services Limited | Administrative & support | 2023 |
| LPM Automotive Ltd | Professional & scientific | 2025 |
| LRN to Drive Limited | Education | 2003 |
| LS Pitchers Limited | Wholesale & retail | 2024 |
| LSS Management Ltd | Construction | 2025 |
| LTG Property Services Ltd | Construction | 2021 |
| LTH Leisure Limited | Arts & recreation | 2020 |
| Lucas & Wyllys Limited | Professional & scientific | 1992 |
| Lucem BMS Ltd | Construction | 2025 |
| Lucky Services Ltd | Manufacturing | 2024 |
| Ludham Garage Limited | Wholesale & retail | 1965 |
| Ludlam Limited | Transport & logistics | 2011 |
| Luhhu Ltd | Information & communication | 2018 |
| Luke Barnes Utilities Limited | Construction | 2024 |
| Lungu Express Delivery Ltd | Transport & logistics | 2026 |
| Lure Fanatics Ltd | Wholesale & retail | 2021 |
| Lusa Limited | Wholesale & retail | 2022 |
| Lusa Restaurant - Bar Limited | Hospitality | 2025 |
| Lynch & Calver Flooring Limited | Wholesale & retail | 2003 |
| Lynway Health and Wellbeing Solutions Ltd | Information & communication | 2017 |
| M & J Properties (Norfolk) Limited | Construction | 2011 |
| M & M 37 Ltd | Hospitality | 2020 |
| M & T Property Development Ltd | Construction | 2025 |
| M B Crewing Services Ltd | Energy | 2015 |
| M C Commercial Cleaning Group Limited | Administrative & support | 2024 |
| M Durrant Transport Limited | Transport & logistics | 2002 |
| M J Bunting Limited | Administrative & support | 2002 |
| M P Taxi's Limited | Transport & logistics | 2024 |
| M&N Taxis Ltd | Transport & logistics | 2014 |
| M. a. Interests Limited | Administrative & support | 2014 |
| M. R. Nichol Accountancy Services Limited | Professional & scientific | 2002 |
| M.D.F. (GT Yarmouth) Ltd. | Wholesale & retail | 1995 |
| M.Lake Holdings Ltd | Wholesale & retail | 2024 |
| Mace Electrical Services Ltd | Construction | 2026 |
| Mach Limited | Hospitality | 2019 |
| MACH2 Recruitment Ltd Limited | Transport & logistics | 2026 |
| Maclennan Motor Group Ltd | Wholesale & retail | 2025 |
| Macron Safety Systems (UK) Limited | Manufacturing | 1974 |
| Macspower Limited | Energy | 2018 |
| Made by Prosper Limited | Professional & scientific | 1993 |
| Magdalene Mini Market Ltd | Wholesale & retail | 2025 |
| Magic Acorns CIC | Arts & recreation | 2019 |
| Magic Brows Ltd | Other services | 2025 |
| Magic Vasilati Ltd | Wholesale & retail | 2021 |
| Magical Pickups Ltd | Wholesale & retail | 2025 |
| Magnetrace Ltd | Manufacturing | 2024 |
| MAH Property Solutions Limited | Real estate | 2020 |
| MAI Builds (East Anglia) Limited | Real estate | 2025 |
| Maid to Shine Ltd | Administrative & support | 2016 |
| Main Cross Garage Services Ltd | Wholesale & retail | 2010 |
| MAJ Financial Planning Ltd | Financial services | 2020 |
| Majestic Amusements Enterprises Limited | Professional & scientific | 1945 |
| Major Fabrications Ltd | Extraterritorial | 2021 |
| Majorspark Limited | Extraterritorial | 2006 |