| Intervest Strategies Ltd | Administrative & support | 2025 |
| Investor Marketplace Limited | Information & communication | 2022 |
| IT Focus Telemarketing Ltd | Administrative & support | 2006 |
| IT Focus Telemarketing Trustee Limited | Administrative & support | 2022 |
| Iwabf Limited | Construction | 2025 |
| J Bragg Home Improvements Limited | Construction | 2022 |
| Jackson & Jones Wines Ltd | Wholesale & retail | 2023 |
| Jake Sullivan Productions Limited | Arts & recreation | 2011 |
| JAM Events Ltd | Hospitality | 2023 |
| Jamie Howarth Ltd | Information & communication | 2018 |
| Jaybeech Property Ltd | Real estate | 2022 |
| JBC Carpentry Ltd | Manufacturing | 2019 |
| Jcmp Limited | Professional & scientific | 2014 |
| Jean-Paul Vuillin Ltd | Administrative & support | 2017 |
| JG Removals Ltd | Transport & logistics | 2020 |
| Jgriffs Ltd | Wholesale & retail | 2024 |
| Jigsaw Property (Bath) Ltd | Construction | 2021 |
| Jill Lindquist Business Services Limited | Professional & scientific | 2003 |
| JLF Brickwork and Driveways Limited | Construction | 2026 |
| JMN Group Holdings Ltd | Financial services | 2023 |
| JMN Homes Leasehold Ltd | Real estate | 2024 |
| JMN Homes Ltd | Real estate | 2023 |
| JOP Environmental Holdings Limited | Financial services | 2020 |
| Kameleon Limited | Professional & scientific | 2009 |
| Kameleon Solutions Limited | Professional & scientific | 2009 |
| Kayra Collection Limited | Hospitality | 2023 |
| Kazson Ltd | Hospitality | 2021 |
| KBM Inspired Ltd | Arts & recreation | 2020 |
| Keensacre Ltd | Professional & scientific | 2022 |
| Kelly-Nairn Consulting Limited | Information & communication | 2022 |
| Kettlesmith Bars Limited | Wholesale & retail | 2021 |
| KH Orkney Ltd | Hospitality | 2018 |
| Kingston Archers Limited | Arts & recreation | 2019 |
| KIT Kline Systems Development Limited | Administrative & support | 2012 |
| KLS Textiles Ltd | Wholesale & retail | 2019 |
| Klwproperty Ltd | Real estate | 2026 |
| KMB Residential Ltd | Real estate | 2025 |
| Kosoler Investments Limited | Households | 1962 |
| Kraytix Limited | Information & communication | 2015 |
| LA Fuga Healthtech Ltd | Professional & scientific | 2024 |
| Landesign Associates Ltd | Professional & scientific | 2014 |
| Laylock Ltd | Manufacturing | 2025 |
| LEE Broderick Communications Ltd | Professional & scientific | 2022 |
| Leesta Ltd | Wholesale & retail | 2016 |
| Lerica Tax Accountants Limited | Professional & scientific | 1998 |
| LH Capital UW Ltd | Real estate | 2020 |
| Lifework Communities Limited | Administrative & support | 2020 |
| Lilasate Limited | Wholesale & retail | 2022 |
| Little Orchard Publishing Ltd | Information & communication | 2024 |
| Little Rituals BOA Ltd | Wholesale & retail | 2023 |
| Look the Business Limited | Information & communication | 2012 |
| LPL Management Limited | Professional & scientific | 2020 |
| Luccombe Limited | Households | 2004 |
| Lucent Consult Limited | Professional & scientific | 2014 |
| Luke Anthony Interiors Ltd | Construction | 2013 |
| Luxeco Holidays Ltd | Administrative & support | 2020 |
| LWM Sporting Consultants Limited | Arts & recreation | 2003 |
| Lycaon Pictures Ltd. | Administrative & support | 2016 |
| Lymore Developments Ltd | Construction | 2026 |
| Lymore Workspaces Ltd | Real estate | 2019 |
| M and C Partners Limited | Information & communication | 2003 |
| M G T Painting and Decorating Ltd | Construction | 2019 |
| M H Investments (South West) Limited | Financial services | 2016 |
| M2 Bespoke Ltd | Information & communication | 2009 |
| Macdonald & Associates Ltd | Professional & scientific | 2017 |
| Made in BOA CIC | Arts & recreation | 2013 |
| Mads & H Limited | Construction | 2016 |
| Mads & O Limited | Construction | 2016 |
| Makepeace-Forster Consulting Ltd | Professional & scientific | 2022 |
| Malaby Holdings Limited | Financial services | 1909 |
| Malaby Martin Limited | Construction | 1949 |
| Malborough Properties Limited | Real estate | 2001 |
| Mandels Ltd | Wholesale & retail | 2023 |
| Marccs Limited | Information & communication | 2002 |
| Marcoms People Ltd | Professional & scientific | 2020 |
| Mary Louise B Ltd | Health & social care | 2011 |
| Matt Poynter Ltd | Information & communication | 2011 |
| Matthew Oliver Weddings Ltd | Administrative & support | 2017 |
| Matthew Tebb Ltd | Manufacturing | 2025 |
| Mcd&A Limited | Professional & scientific | 2023 |
| Medar Investments Ltd | Real estate | 2019 |
| Meg's Cottage Ltd | Hospitality | 2016 |
| Merrell Performance Horses Ltd | Agriculture & fishing | 2026 |
| Merrett Court Melksham Limited | Households | 2022 |
| Mfcs Productions Ltd | Arts & recreation | 2026 |
| Miles Investments Limited | Professional & scientific | 2003 |
| Mission Medicine Ltd | Education | 2019 |
| MJD Catering Limited | Hospitality | 2020 |
| MJT Real Estate Limited | Households | 2024 |
| Mogul Drinks Ltd | Wholesale & retail | 2023 |
| Monsterobot Limited | Information & communication | 2023 |
| Moonraker Ltd | Hospitality | 2025 |
| Moonrakerdi Ltd | Hospitality | 2025 |
| Morfey Limited | Professional & scientific | 2015 |
| Morpheus Nutrition Ltd | Manufacturing | 2025 |
| Moth Media Ltd | Professional & scientific | 2025 |
| Motiveultra Limited | Construction | 1991 |
| Moulton Developments Limited | Manufacturing | 2015 |
| Moulton Group Ltd | Financial services | 2021 |
| MRE Bateman Limited | Health & social care | 2021 |