| Jones Real Estate Empire Limited | Real estate | 2020 |
| Joseph Scragg Architecture Ltd | Construction | 2021 |
| Josh in Accounts Ltd | Professional & scientific | 2025 |
| Joy Paws Dog Hotel Ltd | Other services | 2026 |
| JPB Music Limited | Wholesale & retail | 2004 |
| JPD Forktrucks Ltd. | Manufacturing | 2016 |
| Jpmortgages Ltd | Financial services | 2024 |
| JR Clinical Training & Case Management Ltd | Health & social care | 2021 |
| JR Creative Support Services Ltd | Health & social care | 2022 |
| JSI Consult Ltd | Professional & scientific | 2025 |
| Jskee Properties Ltd | Real estate | 2026 |
| JT Motors Ltd | Wholesale & retail | 2023 |
| JTS Home & Garden Services Ltd | Construction | 2025 |
| Jubilee Square (ST Georges) Management Company Limited | Other services | 2004 |
| Jula Trans Ltd | Transport & logistics | 2019 |
| Jump N Jackz ABC Limited | Arts & recreation | 2017 |
| Junction 21 Motors Ltd | Wholesale & retail | 2024 |
| Jupean Ltd | Administrative & support | 2016 |
| Jurobond Ltd | Real estate | 2021 |
| Just Joscelyn Ltd | Health & social care | 2023 |
| Just One More Ticket Limited | Information & communication | 2023 |
| JUST4ACCESS Ltd | Manufacturing | 2012 |
| Jweeks Management Ltd. | Financial services | 2018 |
| JZK Driving Ltd | Transport & logistics | 2014 |
| K & D Logistics Ltd | Transport & logistics | 2010 |
| K C I Fire Protection Limited | Administrative & support | 2020 |
| K E E Fairs Limited | Extraterritorial | 2023 |
| K ET AL Ltd | Health & social care | 2020 |
| K G Lamb Associates Limited | Real estate | 2016 |
| K J Hobbs Construction Ltd | Construction | 2015 |
| K Lakey Consulting Ltd | Professional & scientific | 2025 |
| K M Garage W-S-M Ltd | Wholesale & retail | 2023 |
| K Martin Smith Ltd | Hospitality | 2025 |
| K Palmer Memorials Ltd | Manufacturing | 2018 |
| K W Flooring Limited | Construction | 2017 |
| K Worle Barber 3 Limited | Other services | 2025 |
| K&A Plumbing & Heating Limited | Construction | 2000 |
| K.J.L.Interiors Ltd | Construction | 2021 |
| K.M.Neads Property Ltd | Real estate | 2025 |
| K.S Repair Ltd | Wholesale & retail | 2026 |
| Kabelec Electrical Services Limited | Construction | 2007 |
| Kabukabu Online Services Ltd | Information & communication | 2023 |
| Kacper's Custom Works Ltd | Wholesale & retail | 2022 |
| Kaczor CAB Ltd | Transport & logistics | 2026 |
| KAE Connect Ltd | Administrative & support | 2017 |
| Kaleidoscope Multi Academy Trust | Education | 2017 |
| Kampitvan Limited | Manufacturing | 2017 |
| KAN Engineering (SW) Ltd | Manufacturing | 2012 |
| Kapoors Properties Limited | Wholesale & retail | 2018 |
| Kaps Health Care Ltd | Health & social care | 2024 |
| Karina Industry Ltd | Transport & logistics | 2026 |
| Karteno Ltd | Wholesale & retail | 2022 |
| Karuna Bridges Limited | Health & social care | 2025 |
| Karuta Sportswear Ltd | Manufacturing | 2016 |
| Katalyst Consultancy Ltd | Professional & scientific | 2019 |
| Kate Edwards Consulting Limited | Administrative & support | 2015 |
| Katseye Media Ltd | Administrative & support | 2022 |
| Katw 2020 Limited | Hospitality | 2020 |
| Kayzekc Ltd | Health & social care | 2022 |
| KB Interiors (WSM) Ltd | Construction | 2024 |
| KBM Automotive Ltd | Wholesale & retail | 2023 |
| KBM Leisure Ltd | Hospitality | 2021 |
| KBM Trading Ltd | Wholesale & retail | 2021 |
| Kbmo Diagnostics Ltd | Professional & scientific | 2021 |
| KC Advisory Management Limited | Water & waste | 2014 |
| KC Flowmetering Ltd | Administrative & support | 2024 |
| KCBS23 Ltd | Households | 1971 |
| KCI Fire Doors Ltd | Administrative & support | 2024 |
| KDC Kitchens Ltd | Wholesale & retail | 2021 |
| Kedib Consulting Limited | Professional & scientific | 2025 |
| Keepers Gate Forest School Ltd | Education | 2021 |
| Kelston Gardens Residents Company Limited | Households | 1989 |
| Kenick Services Limited | Construction | 2004 |
| Kenim Builders Ltd | Construction | 2025 |
| Kennard Brothers Limited | Construction | 2021 |
| Kenny Care Services Limited | Health & social care | 2025 |
| Kenwei Ltd | Hospitality | 2024 |
| Keran Mellor Services Limited | Construction | 1998 |
| Kerb Media Ltd | Information & communication | 2025 |
| Kerek Homes Ltd | Real estate | 2025 |
| Kevin Burgess Limited | Administrative & support | 2025 |
| Kevin Ogston Accountancy Services Ltd | Professional & scientific | 2026 |
| KEW Gardens Management Company Limited | Households | 2016 |
| Kewstoke Motor Services Ltd | Wholesale & retail | 2013 |
| Key Creative Limited | Real estate | 2020 |
| Key Properties (SW) Limited | Real estate | 2010 |
| Key Solutions Mortgages Limited | Financial services | 1995 |
| Keystone IT Solutions Ltd | Information & communication | 2026 |
| KFB Keynsham Ltd | Hospitality | 2024 |
| KFH Property Investments Ltd | Real estate | 2023 |
| KGD Developments Ltd | Real estate | 2021 |
| KH BIO Cleaning Ltd | Administrative & support | 2019 |
| Khao Thai 1 Limited | Hospitality | 2025 |
| Khon Tong Limited | Other services | 2021 |
| Khronos Limited | Real estate | 2021 |
| Kidsville (WSM) Ltd | Arts & recreation | 2016 |
| Kikki & Fletch Limited | Hospitality | 2022 |
| Kilminster Flats (Weston-Super-Mare) Limited | Professional & scientific | 1983 |
| Kilmix Media Limited | Information & communication | 2025 |
| Kindkeys Care Ltd | Health & social care | 2023 |