| JGR Accounting Solutions Limited | Professional & scientific | 2012 |
| JGS Property Investments Limited | Real estate | 2021 |
| Jigsaw Engage Limited | Professional & scientific | 2025 |
| Jjoc Ltd | Real estate | 2017 |
| JLH Property Management & Consultancy Limited | Construction | 2023 |
| JMG Associates Limited | Administrative & support | 2008 |
| Joinspot Property Management Limited | Households | 1990 |
| Josa Projects Limited | Professional & scientific | 2018 |
| Joulemiser Limited | Extraterritorial | 2018 |
| Journey With Nikita Ltd | Health & social care | 2023 |
| Joya Property Ventures Limited | Real estate | 2020 |
| JP Race Events Ltd | Professional & scientific | 2021 |
| JR Consulting & Strategy Limited | Professional & scientific | 2025 |
| JR Smart Solutions Limited | Transport & logistics | 2018 |
| Judeson Ltd | Professional & scientific | 2019 |
| Just Love by Aziz Limited | Health & social care | 2025 |
| JW Online Ltd | Health & social care | 2022 |
| JWH Hospitality Solutions Limited | Professional & scientific | 2015 |
| K and K Finishing Limited | Manufacturing | 2019 |
| K&D Healthcare Consultancy Ltd | Hospitality | 2019 |
| K.P Plant Repairs Ltd | Manufacturing | 2021 |
| KA Learning & Coaching Ltd | Professional & scientific | 2025 |
| KALQL8 Limited | Professional & scientific | 2022 |
| Kamble Creative Ltd | Information & communication | 2017 |
| Kamil Bieniek - Eco Shine Ltd. | Administrative & support | 2020 |
| Karma Flooring (South East) Limited | Construction | 2022 |
| Kaytchi Limited | Professional & scientific | 2020 |
| Kean HR Limited | Professional & scientific | 2005 |
| Kenison Consulting Ltd | Information & communication | 2016 |
| Key Communications Ltd | Information & communication | 2025 |
| Kilmington Close Residents Association Limited | Households | 1987 |
| Kingsley Property Ltd | Real estate | 2017 |
| Kingswood (Shute END) Management Company Limited | Households | 2004 |
| Kipling Hall Management Co. Limited | Real estate | 2004 |
| Knight Light Ltd | Construction | 2023 |
| Knowitall Ninja Limited | Education | 2022 |
| Knowledge MAP Limited | Extraterritorial | 2000 |
| Konsult Pharma Services Limited | Professional & scientific | 2014 |
| L.Cara Management Limited | Professional & scientific | 2023 |
| LA Building and Construction Limited | Construction | 2021 |
| LA Corporation Limited | Construction | 2020 |
| Ladder World Limited | Administrative & support | 2025 |
| Lakshman Consultancy Ltd | Information & communication | 2013 |
| Langton Estates Limited | Construction | 2007 |
| Larkspur Equestrian Ltd | Education | 2013 |
| Larkspur Equitation LLP | | 2018 |
| Lars Luno Limited | Health & social care | 2020 |
| Launch Consulting Group Ltd | Professional & scientific | 2021 |
| Launch Consulting MWH Ltd | Professional & scientific | 2020 |
| Launch Loop Ltd | Information & communication | 2025 |
| Lavant Accountants Ltd | Professional & scientific | 2021 |
| Lazy B'S Barbers Ltd | Other services | 2018 |
| LB Property Maintenance Ltd | Manufacturing | 2021 |
| LBS Barbers Ltd | Other services | 2024 |
| LDI Project Solutions Limited | Professional & scientific | 2013 |
| LDP Consultancy Ltd | Financial services | 2014 |
| LE Pomme Limited | Professional & scientific | 2022 |
| Lear Chiropractic Limited | Health & social care | 2014 |
| Legion Consultants Limited | Information & communication | 2016 |
| Lemming Enterprises Ltd | Education | 2022 |
| Lemon Source Consultancy Ltd | Professional & scientific | 2026 |
| Lemontee Consulting Limited | Professional & scientific | 2014 |
| Lending Matters Limited | Financial services | 2018 |
| Leonvz Ltd | Other services | 2010 |
| Letcombe Court Limited | Households | 1996 |
| Letters to Finley Limited | Wholesale & retail | 2024 |
| Lever Innovations Ltd | Professional & scientific | 2019 |
| Levitikal Ready MIX Concrete & Construction Limited | Manufacturing | 2024 |
| LFT Systems Ltd | Construction | 2024 |
| Liberty Court (Roundswell) Management Company Limited | Real estate | 2005 |
| Lifetime Software Limited | Information & communication | 2001 |
| Lightwater Spice Ltd | Hospitality | 2025 |
| Linden Waterloo Engineering | Professional & scientific | 2010 |
| Lisboa Consulting Ltd | Information & communication | 2025 |
| Lissbury Capital Limited | Financial services | 2020 |
| Little Acorns Montessori Limited | Health & social care | 2013 |
| LIZ Patey Hair & Make-Up Ltd | Other services | 2026 |
| LJB Props Ltd | Information & communication | 2025 |
| Local Software Limited | Information & communication | 1994 |
| Lodge-I-Cal Ltd | Construction | 2022 |
| Logic 365 Ltd | Information & communication | 2007 |
| Loic’S Deli Ltd | Wholesale & retail | 2021 |
| Longdown Lodge Limited | Households | 1990 |
| Lorraine's Emporium Ltd | Wholesale & retail | 2008 |
| Lottie Crocker Horses & Tack Shop Limited | Agriculture & fishing | 2018 |
| Loulou's Crafts and More Ltd | Wholesale & retail | 2024 |
| Loupaper Limited | Manufacturing | 2019 |
| Lumartech Ltd | Wholesale & retail | 2014 |
| Lupin Management Services Ltd | Professional & scientific | 2008 |
| Luxury Sustainable Homes (South) Ltd | Construction | 2024 |
| LW Crash Repair Consultants Ltd | Wholesale & retail | 2023 |
| Lyon Road Freehold Owners Ltd | Real estate | 2023 |
| M B Building Works Ltd | Construction | 2010 |
| M.V.M Barbers Ltd | Other services | 2026 |
| Macmanus Music Project Ltd | Arts & recreation | 2023 |
| Maco Total Construction Ltd | Construction | 2026 |
| Made by Mandi Limited | Wholesale & retail | 2026 |
| Magby Limited | Wholesale & retail | 2022 |
| Magikos IT Limited | Administrative & support | 2012 |
| Magis Global Limited | Professional & scientific | 2015 |