| KJB Models Ltd | Wholesale & retail | 2021 |
| Klin Klans Thai Cuisine Limited | Hospitality | 2025 |
| KM & Co. Holdings Ltd | Financial services | 2025 |
| KM Home Improvements Limited | Construction | 2023 |
| KNG Street Southport Leasehold 57 Ltd | Real estate | 2025 |
| Knight Industries Limited | Manufacturing | 2023 |
| Knight's Gifts Ltd | Manufacturing | 2025 |
| Knights Wetrooms Ltd | Construction | 2024 |
| Knighttree Limited | Construction | 2016 |
| Knoll Pictures Limited | Information & communication | 2025 |
| KOK Transport Services Ltd | Transport & logistics | 2023 |
| Koniarzproperties Ltd | Real estate | 2025 |
| KP Alpha Builds Ltd | Construction | 2026 |
| KP Ecology Ltd | Professional & scientific | 2011 |
| KPS Groundworks Ltd | Construction | 2005 |
| Krianth Limited | Health & social care | 2025 |
| Krishvik Limited | Real estate | 2025 |
| Kristina Sestokaite Ltd | Health & social care | 2024 |
| Kstarr Limited | Administrative & support | 2020 |
| Ktrz Software Limited | Information & communication | 2008 |
| Kurdish Barber Dorset Ltd | Other services | 2024 |
| Kurt Mueller (U.K.) Limited | Manufacturing | 1950 |
| Kustomvans Ltd | Wholesale & retail | 2021 |
| L Burns Plumbing and Heating Limited | Professional & scientific | 2011 |
| L C Marine Services Limited | Transport & logistics | 2013 |
| L C Wills Contracts Limited | Construction | 1999 |
| L Morgan Business Solutions Limited | Professional & scientific | 2016 |
| L S Williams Carpentry & Renovations Ltd | Extraterritorial | 2017 |
| L&M Project Management Ltd | Construction | 2024 |
| L.A. Management LLP | | 2005 |
| L.S Electrical (SW) Limited | Manufacturing | 2019 |
| L14 A10 Limited | Real estate | 2020 |
| L2R Print Ltd | Manufacturing | 2023 |
| LA Coastal Boatworks Ltd | Manufacturing | 2023 |
| LA Luna (Weymouth) Limited | Administrative & support | 2000 |
| LA Poole Limited | Real estate | 2015 |
| LAB Design and Consultancy Ltd | Professional & scientific | 2025 |
| Labonitaweymouth Ltd | Hospitality | 2025 |
| Laguna Blue Ltd | Manufacturing | 2018 |
| Laika Creative Limited | Information & communication | 2006 |
| Lake Developments (Weymouth) Limited | Construction | 2014 |
| Lake GAS Consultancy Ltd | Education | 2026 |
| Lakeside Cyber Risk Consulting (International) LP | | 2017 |
| Lambert Properties Weymouth Ltd | Construction | 2024 |
| Laming & Sons Ltd. | Construction | 1971 |
| Laming & Wills Developments Limited | Construction | 2017 |
| Landmark Studio Limited | Professional & scientific | 2017 |
| Lane Love Limited | Financial services | 1985 |
| Lanehouse Service Station Limited | Wholesale & retail | 1962 |
| Langford Developments Limited | Real estate | 2020 |
| Langham Hotel Limited | Hospitality | 2003 |
| Lansdowne Lodge (Weymouth) Management Limited | Other services | 2002 |
| Lansdowne Square Management Company Ltd | Households | 2016 |
| Lansdowne Villa Management Company Limited | Households | 1988 |
| Lara Mobile Unisex Hairdresser Ltd | Other services | 2021 |
| Laura Moore HR Limited | Administrative & support | 2023 |
| Lauren Bannon Music Ltd | Information & communication | 2021 |
| Lawrence Mccarthy Gates & Railings Limited | Manufacturing | 2010 |
| Layzell Solicitors Limited | Real estate | 2007 |
| Lbpa Limited | Arts & recreation | 2022 |
| LC Electric Contractors Limited | Construction | 2020 |
| LC Tech Limited | Professional & scientific | 2020 |
| Leather-Restoration Limited | Wholesale & retail | 2015 |
| LEE Read Plumbing and Heating Limited | Construction | 2019 |
| LEE Stebbing Plumbing and Heating LLP | | 2005 |
| LEE Wills Holdings Limited | Construction | 2003 |
| Leeson Partnership Ltd | Construction | 2013 |
| Legacy Magazines Ltd | Information & communication | 2011 |
| Legacy Management (SW) Ltd | Households | 2026 |
| Legendary Fitness Ltd | Arts & recreation | 2024 |
| Leisure Vehicle Care Limited | Wholesale & retail | 2022 |
| Leisureranch Limited | Arts & recreation | 2002 |
| Lekdev Limited | Administrative & support | 2016 |
| LEO Court Limited | Real estate | 2012 |
| LES Enfants Terribles Restaurant Ltd | Hospitality | 2019 |
| Lesley Boyle Limited | Professional & scientific | 2018 |
| Leto Composites Limited | Extraterritorial | 2013 |
| Lewis Electrical UK Limited | Construction | 2008 |
| Lewis Stoneworks Limited | Manufacturing | 2015 |
| Lewitt Technologies Ltd | Professional & scientific | 2019 |
| LF PMU Limited | Other services | 2019 |
| Lflf Ltd | Real estate | 2024 |
| Libre Living Holdings Limited | Real estate | 2023 |
| Libre Living Homecare Ltd | Health & social care | 2010 |
| Libre Living Limited | Health & social care | 2008 |
| Licensed Victuallers' Trade Association (West) | Other services | 1992 |
| Limelight Boutique Weymouth Ltd | Wholesale & retail | 2019 |
| Limelight Footwear Limited | Wholesale & retail | 2021 |
| Liming Harry's Ltd | Hospitality | 2026 |
| Limitless Electrical Services Ltd | Construction | 2018 |
| Lionheart Graphics Limited | Professional & scientific | 1997 |
| Lionslamb PUB Co Limited | Health & social care | 2026 |
| Lisdoonie Limited | Real estate | 2021 |
| Little Delwood Ltd | Education | 2018 |
| Littlemoor Estate Management Client Company Limited | Real estate | 1986 |
| Littlemoor Green Hands CIC | Other services | 2025 |
| Littlemoor Tandoori Ltd | Hospitality | 2022 |
| LJ Finishers Limited | Construction | 2026 |
| LJC Trading Ltd | Wholesale & retail | 2021 |
| LJP Detailing Ltd | Administrative & support | 2024 |