| Kersfield Limited | Construction | 2016 |
| Kerve Creative Ltd | Arts & recreation | 2008 |
| KES Bath Ventures Limited | Administrative & support | 2026 |
| Kevin Baldwin Limited | Construction | 2004 |
| Key Main Developments Limited | Construction | 1992 |
| Key Medical Ltd | Health & social care | 2012 |
| Keyford Meadows Residents Management Company Limited | Households | 2023 |
| Keynsham Motors Limited | Wholesale & retail | 2024 |
| Keystone AI Ltd | Information & communication | 2025 |
| Keystone Drives & Patios Specialist Ltd | Construction | 2026 |
| Kezebo Ltd | Information & communication | 2025 |
| KF (Personal Taxation) Limited | Professional & scientific | 2000 |
| KG Flooring Ltd | Construction | 2023 |
| KG Sports Associates Limited | Professional & scientific | 2017 |
| KGS Cardiology Ltd | Health & social care | 2019 |
| Khighs Ltd | Wholesale & retail | 2023 |
| Kidd and Bear Ltd | Manufacturing | 2016 |
| Kildare Flats (Bath) Limited | Households | 1978 |
| Kiln Creative Ltd | Professional & scientific | 2022 |
| Kilpin & Co. Ltd | Construction | 2025 |
| Kilter Theatre | Arts & recreation | 2008 |
| Kimble Trading Limited | Administrative & support | 2003 |
| Kimblesworth Solar Limited | Energy | 2021 |
| Kimisa Limited | Real estate | 2020 |
| Kimiti Audio Ltd | Information & communication | 2020 |
| Kinden Ltd | Real estate | 2020 |
| Kinergy | Health & social care | 2002 |
| Kingcross Limited | Construction | 1973 |
| Kingdom Prospects Ltd | Financial services | 2018 |
| Kingfisher Academy Ltd | Arts & recreation | 2024 |
| Kingfisher and Kyte Limited | Professional & scientific | 2019 |
| Kingfisher Blinds (Bath) Limited | Other services | 2013 |
| Kingfisher Family Mediation Ltd | Health & social care | 2025 |
| Kingfisher TT Limited | Wholesale & retail | 2023 |
| Kingman Joinery Limited | Construction | 2014 |
| Kingsbury Homes (Holdings) Limited | Wholesale & retail | 2019 |
| Kingsgate Consultants Ltd | Professional & scientific | 2020 |
| Kingsgate Investing Limited | Real estate | 2022 |
| Kingsgate Management Advisory Limited | Professional & scientific | 2024 |
| Kingsmead Tasty Kitchen Ltd | Hospitality | 2025 |
| Kingston by Design Limited | Wholesale & retail | 2012 |
| Kingswood Enterprises Limited | Administrative & support | 1990 |
| Kingswood International Limited | Education | 2016 |
| Kingswood School Trustee Limited | Education | 2001 |
| Kingwell Finance Ltd | Professional & scientific | 2020 |
| Kinnaird Keble Developments Limited | Real estate | 2019 |
| Kipling Kent Limited | Professional & scientific | 2017 |
| Kirkness House Limited | Households | 2002 |
| Kiss of Life Productions Company Ltd | Arts & recreation | 2020 |
| Kitani Ltd | Wholesale & retail | 2023 |
| Kitcamp Limited | Wholesale & retail | 2015 |
| Kitchen Fitters Bath Ltd | Construction | 2014 |
| Kitchens of Bath Limited | Construction | 2012 |
| Kittiwake Limited | Professional & scientific | 2023 |
| KJ PAY Limited | Professional & scientific | 2024 |
| KJ Rendering Ltd | Construction | 2021 |
| Kjakub Ltd | Construction | 2025 |
| KJG Medical Ltd | Health & social care | 2013 |
| KL Software Design Limited | Information & communication | 2025 |
| Klarica Limited | Information & communication | 2024 |
| Klas Property Developers Ltd | Real estate | 2024 |
| KLG Media Consultants Ltd | Professional & scientific | 2012 |
| Klin Design Ltd | Professional & scientific | 2022 |
| Klood Digital Ltd | Administrative & support | 2017 |
| Klose Ltd | Information & communication | 2024 |
| KLP Acquisitions Limited | Wholesale & retail | 2025 |
| Kludoc Limited | Health & social care | 2006 |
| KM One Bath Limited | Hospitality | 2018 |
| KMK Chauffeurs Ltd | Transport & logistics | 2021 |
| KML Event Management Limited | Administrative & support | 2010 |
| Kmoylan Pubco Ltd | Hospitality | 2025 |
| KMS Property Rental Ltd | Real estate | 2019 |
| KN Business Development Ltd | Professional & scientific | 2026 |
| KN Roofing and Building Ltd | Construction | 2026 |
| Knifty Ltd | Wholesale & retail | 2020 |
| Knight Price Ventures Limited | Construction | 2015 |
| Known and Cited Ltd | Information & communication | 2026 |
| Koach Media Ltd | Wholesale & retail | 2019 |
| Kobsz Limited | Professional & scientific | 2020 |
| Kode Historic Ltd | Construction | 2022 |
| Kodeworks Limited | Information & communication | 2021 |
| Kong Bloodstock Ltd | Agriculture & fishing | 2024 |
| Koolsystems Ltd | Construction | 2024 |
| Kooltech Trailers Limited | Other services | 2019 |
| Koop Design Ltd | Professional & scientific | 2013 |
| Koru Clothing Ltd | Wholesale & retail | 2006 |
| Kosher Music Limited | Construction | 2022 |
| Koterra Limited | Real estate | 2025 |
| KPK Construction Ltd | Real estate | 2023 |
| Krazi ROX Limited | Real estate | 2016 |
| KRH Marketing Ltd | Professional & scientific | 2026 |
| Kris' Barber Shop Limited | Other services | 2019 |
| Kritya Healthcare Ltd | Health & social care | 2018 |
| Kroma Services Ltd | Health & social care | 2015 |
| Kronopac Limited | Professional & scientific | 2007 |
| KSM Consultancy Services Ltd | Professional & scientific | 2026 |
| KT Contract Solutions Ltd | Administrative & support | 2019 |
| KTM Boats Bath Limited | Transport & logistics | 2017 |
| Kubecode Limited | Information & communication | 2024 |
| Kuberry Ltd | Information & communication | 2019 |