| KP, NP & LL Company Limited | Real estate | 2016 |
| KPH Advisory Ltd | Professional & scientific | 2012 |
| Kraken Yachts Limited | Wholesale & retail | 2017 |
| Krav Maga Education Limited | Education | 2013 |
| Krav Maga Elite Ltd | Education | 2025 |
| Kreatie Limited | Administrative & support | 2012 |
| Kri-Pan Estates Ltd | Real estate | 2023 |
| Krifey Ltd | Wholesale & retail | 2020 |
| Krigo Ltd | Information & communication | 2026 |
| KRK Electrical Ltd | Construction | 2025 |
| Kromatek Limited | Wholesale & retail | 2000 |
| Kronen Bond Limited | Transport & logistics | 2016 |
| Krpz Logistics Limited | Transport & logistics | 2025 |
| KRS Holdco Limited | Real estate | 2021 |
| KS Farming Ltd | Agriculture & fishing | 2024 |
| KS Nadlan Ltd | Real estate | 2026 |
| KSE Services Limited | Construction | 1998 |
| KSK Homes Ltd | Real estate | 2020 |
| KSS Productions Ltd | Information & communication | 2023 |
| KT Accounts & Tax Limited | Real estate | 2013 |
| KT Management & Project Services Limited | Hospitality | 2018 |
| Kt&Mja Solar Ltd | Construction | 2023 |
| KTN Surfacing Ltd | Construction | 2024 |
| Kttc Limited | Transport & logistics | 2021 |
| Kubi Transport Ltd | Transport & logistics | 2023 |
| Kudocs Limited | Information & communication | 2015 |
| Kudocs Registered Office Services Ltd | Information & communication | 2021 |
| Kudocs Test Premium Share Limited | Information & communication | 2023 |
| Kudocs Testing 3 Limited | Information & communication | 2021 |
| Kudocs Testing LBG Ltd | Information & communication | 2020 |
| Kudocs Testing Limited | Information & communication | 2016 |
| Kudos Home Improvements Limited | Construction | 2023 |
| Kudsi Plumbing and Heating Ltd | Construction | 2022 |
| Kuker Ltd | Wholesale & retail | 2018 |
| Kumar & Kaushal Ltd | Health & social care | 2026 |
| Kumar Strategic Consultants Ltd | Professional & scientific | 2008 |
| Kumon Riverside Baddow LLP | | 2024 |
| Kurtlar Ltd | Manufacturing | 2020 |
| Kuszneruk Ltd | Other services | 2018 |
| KV Marble & Granite Ltd | Manufacturing | 2017 |
| Kwatee Ltd | Professional & scientific | 2017 |
| Kwickpack Limited | Administrative & support | 2015 |
| KY Engineering Ltd | Professional & scientific | 2018 |
| KYS Properties PVT Ltd | Real estate | 2024 |
| Kyveon Ltd | Households | 2025 |
| L & Co Exteriors Ltd | Administrative & support | 2023 |
| L & L Football Limited | Arts & recreation | 2023 |
| L & L Property Investments Ltd | Real estate | 2024 |
| L & M Auto Repairs Limited | Wholesale & retail | 2023 |
| L B J Holdings Limited | Real estate | 2019 |
| L B Piling Limited | Construction | 2021 |
| L Detachment Group Limited | Real estate | 2017 |
| L K Utility Services Ltd | Construction | 2018 |
| L M Painters Ltd | Construction | 2017 |
| L M Safety Installations Ltd | Construction | 2022 |
| L Rose Interiors Ltd | Professional & scientific | 2017 |
| L&A Advisory Ltd | Professional & scientific | 2026 |
| L&C EST Ltd | Wholesale & retail | 2025 |
| L&G Events Hire Ltd | Other services | 2023 |
| L&H Consulting LLP | | 2021 |
| L&H Management Ltd | Administrative & support | 2015 |
| L&L Properties Ltd | Real estate | 2025 |
| L&R Renewables Ltd | Construction | 2021 |
| L.B. & F. Ltd | Construction | 2008 |
| L.B. & F. Specialist Facades Ltd | Construction | 2018 |
| L.C. (Gemini) Limited | Construction | 2014 |
| L.C. (Godfreys) Ltd | Construction | 2014 |
| L.C.(Stevenage) Ltd | Construction | 2015 |
| L.F.Home & Garden Ltd | Construction | 2025 |
| L.J.M. Engineering LLP | | 2016 |
| L.O.P Commercial Ltd | Administrative & support | 2024 |
| L.P. Foreman & Sons Limited | Manufacturing | 1995 |
| L3 Leisure Limited | Hospitality | 2020 |
| L3 Property Limited | Financial services | 2013 |
| L8 Datanet Ltd | Information & communication | 2013 |
| LA Careers Ltd | Administrative & support | 2025 |
| LA Estetica Distribution Ltd | Wholesale & retail | 2021 |
| LA Rocca Holding Ltd | Financial services | 2026 |
| LA Rochelle Essex Ltd | Health & social care | 2022 |
| LA Specialist Occupational Therapy Assessments Limited | Health & social care | 2025 |
| LA Wallace Floristry Limited | Wholesale & retail | 2026 |
| Laburnham Property Co Limited | Real estate | 2017 |
| Labx Solutions Limited | Manufacturing | 2024 |
| Lacc Business Synergy Limited | Wholesale & retail | 2022 |
| Lacc Homes Ltd | Real estate | 2022 |
| Lace: Life After Cancer Essex CIC | Other services | 2022 |
| Lacey's Motorcycles Limited | Wholesale & retail | 2021 |
| Laco Group Limited | Financial services | 2024 |
| Ladan Services Ltd | Financial services | 2024 |
| Lady Lightning Ltd | Real estate | 2019 |
| Ladylo Distributors Limited | Extraterritorial | 2014 |
| Lagnoak Limited | Manufacturing | 2025 |
| Lahore Trading International Limited | Wholesale & retail | 2010 |
| Laidback Beds Limited | Wholesale & retail | 2017 |
| Laircroft Limited | Construction | 1991 |
| Lajna Dawah Islamia Limited | Education | 2024 |
| Lake Avenue Limited | Wholesale & retail | 2015 |
| Lake Electrical Services Limited | Construction | 2019 |
| Lakefront Care Services Ltd | Health & social care | 2017 |
| Lakeshield Property Services Limited | | 2009 |