| Ivor Creek Limited | Real estate | 1956 |
| Izinduna Enterprises Ltd | Information & communication | 2015 |
| J & a Williams & Sons Limited | Agriculture & fishing | 2020 |
| J C Taylor Developments Limited | Real estate | 2025 |
| J C Taylor Holdings Limited | Financial services | 2025 |
| J Crighton Limited | Wholesale & retail | 2024 |
| J Pearse & Sons Limited | Transport & logistics | 2022 |
| J&J Bull Associates Ltd | Hospitality | 2021 |
| J.F. Clarke & SON Limited | Extraterritorial | 2003 |
| J.G. Restorick Properties Management Ltd | Extraterritorial | 2016 |
| Jaffe ET Fils Limited | Manufacturing | 2003 |
| James Clampin Heating & Plumbing Ltd | Construction | 2025 |
| Jamie Orr-Ewing Limited | Manufacturing | 2016 |
| JB Property Improvements Limited | Construction | 2026 |
| JBR Property Group Limited | Real estate | 2025 |
| Jbwm Ltd | Real estate | 2022 |
| JC Plumbing & Heating Ltd | Construction | 2019 |
| JC Taylor Residential Limited | Real estate | 2017 |
| JCC Machinery Limited | Wholesale & retail | 2023 |
| JCS Dorset Limited | Administrative & support | 2025 |
| JDC Optical Limited | Health & social care | 2020 |
| Jeeves (South West) Ltd | Arts & recreation | 2013 |
| Jessica Blume Ltd | Wholesale & retail | 2023 |
| Jevilla Limited | Households | 2026 |
| JJ Engineering (SW) Limited | Manufacturing | 2012 |
| JJB Gardens Ltd | Administrative & support | 2023 |
| Jjoc Structures Ltd | Professional & scientific | 2022 |
| JOE Stork Ltd | Information & communication | 2021 |
| Joined Apps Limited | Construction | 2017 |
| JON J Oates Ltd | Construction | 2010 |
| JPL Heating & Plumbing Ltd | Construction | 2024 |
| JRS Logistics Limited | Wholesale & retail | 2019 |
| Julian Hill Electrical Ltd | Construction | 2025 |
| Jurassic Coast Cleaning Company Ltd | Administrative & support | 2019 |
| Jurassic Coast Developments Ltd | Construction | 2017 |
| Jurassic Saunas Limited | Health & social care | 2026 |
| Jurassic Services Ltd | Administrative & support | 2020 |
| JWB Construction Ltd | Construction | 2023 |
| JWB Developments Ltd | Construction | 2017 |
| K C Joinery Limited | Construction | 2003 |
| Kadel Solutions Limited | Professional & scientific | 2002 |
| Kankei Limited | Professional & scientific | 2006 |
| Kassia Fusion Ltd | Hospitality | 2025 |
| Keep Camping Ltd | Wholesale & retail | 2023 |
| Keith Perryman Electrical Contractors Limited | Construction | 2003 |
| Kemm's VEG Limited | Wholesale & retail | 2018 |
| Kentmere (Holdings) Limited | Real estate | 2010 |
| Keppel Place Development Ltd | Construction | 2021 |
| Kilmington Cross Garage Ltd | Wholesale & retail | 2017 |
| Kilmington Self Storage Limited | Hospitality | 2011 |
| Kings Plumbing and Electrical Ltd | Construction | 2019 |
| Kingsgreen Estates Ltd | Real estate | 2024 |
| Kingsley Landscaping Ltd | Administrative & support | 2020 |
| Kinnami Software Corporation Limited | Information & communication | 2018 |
| Kireya Property Group Ltd | Real estate | 2025 |
| Kitty-Williams Limited | Wholesale & retail | 2007 |
| KMN Tregothnan Limited | Households | 2005 |
| KOA Tonewood Ltd | Wholesale & retail | 2021 |
| Kobo Living Ltd | Wholesale & retail | 2021 |
| Kobocrete Limited | Manufacturing | 2013 |
| Koyo Healthtech Ltd | Information & communication | 2024 |
| Ksdb Holdings Limited | Construction | 2023 |
| Lamorne Development Ltd | Construction | 2024 |
| Langford Construction (SW) Limited | Construction | 2023 |
| Larcombe & Markham Ltd | Construction | 2017 |
| Lawrence Contractors Devon Ltd | Construction | 2018 |
| Lawrence EHC Ltd | Professional & scientific | 2002 |
| Lawson Computer Repair Ltd | Other services | 2021 |
| LBW Drinks Ltd. | Manufacturing | 1993 |
| LE Centre Limited | Professional & scientific | 2005 |
| LE Pisani (Holdings) Limited | Real estate | 2021 |
| LE Pisani (Seaton) Limited | Hospitality | 2018 |
| LE Tennis Limited | Arts & recreation | 2002 |
| LEA Place Management Company Limited | Households | 2015 |
| Lead Business Management Services Ltd | Professional & scientific | 2018 |
| Lemon Plaice (Axminster) Limited | Hospitality | 2014 |
| Lets Go Holidays Limited | Administrative & support | 2017 |
| Lightpath Optical (UK) Limited | Manufacturing | 2003 |
| Lilac Cottage Larder Ltd | Agriculture & fishing | 2020 |
| Lindseytye Limited | Professional & scientific | 2004 |
| Little Orchard Alpacas Ltd | Agriculture & fishing | 2016 |
| Lloyd Builders Investments Limited | Real estate | 2003 |
| Lmgi Ltd | Wholesale & retail | 2020 |
| Longhill Heritage Ltd | Wholesale & retail | 2013 |
| LOU LA Belle (Axminster) Limited | Wholesale & retail | 2025 |
| Ltms Ltd | Professional & scientific | 1981 |
| Lyme Bay Fisherman's CIC | Professional & scientific | 2022 |
| Lyme Bay Huts Limited | Construction | 2023 |
| Lyme Bay Logistics Ltd | Transport & logistics | 2024 |
| Lyme Bay Plumbing & Heating Ltd | Construction | 2021 |
| Lyme Bay Properties Limited | Real estate | 2021 |
| Lyme Bay Property Limited | Real estate | 2014 |
| Lyme Regis Bespoke Interiors Ltd | Manufacturing | 2018 |
| Lyme Rocks Ltd | Wholesale & retail | 2018 |
| Lyme Time Travellers Ltd | Wholesale & retail | 2023 |
| Lymearts Commmunity Trust Limited | Arts & recreation | 2003 |
| M C R Developments Limited | Real estate | 1996 |
| Machinne Ltd | Professional & scientific | 2016 |
| Mack Management Ltd | Hospitality | 2025 |
| Mack Property Services Ltd | Manufacturing | 2023 |