| JSK Nandda Ltd | Transport & logistics | 2022 |
| Jsuppal Transport Limited | Transport & logistics | 2021 |
| JSW Freight Ltd | Transport & logistics | 2007 |
| JTA Scaffolding Services Limited | Construction | 2011 |
| Jubilee Automotive Group Limited | Manufacturing | 1992 |
| Jubilee Pharmacy Limited | Wholesale & retail | 2014 |
| Jukes Trading Limited | Extraterritorial | 2025 |
| Julia’S Flowers Ltd | Wholesale & retail | 2020 |
| Jupiter Practice Ltd | Health & social care | 2025 |
| Just Peugeots [WM] Ltd | Wholesale & retail | 2021 |
| Just to SAY LLP | | 2010 |
| JW Pool and Grill Limited | Arts & recreation | 2026 |
| JWH Business Services Ltd | Professional & scientific | 2018 |
| JX Holistic Property & Wellbeing Ltd | Administrative & support | 2025 |
| JXH Ltd | Transport & logistics | 2025 |
| K & M Flooring Limited | Construction | 2003 |
| K D Property Rentals Ltd | Real estate | 2018 |
| K HD PUB 23 Ltd | Hospitality | 2023 |
| K K Care Recruitment Ltd | Health & social care | 2013 |
| K&S Scaffolding WM Ltd | Construction | 2026 |
| K.J. Andrews Ltd | Arts & recreation | 2017 |
| K.L. Food Processing Consultants Ltd | Professional & scientific | 2021 |
| K.V. Steel Services Limited | Manufacturing | 2002 |
| K9 Guards Ltd | Administrative & support | 2022 |
| K9 New World Order Ltd | Administrative & support | 2019 |
| K9 NWO Ltd | Administrative & support | 2019 |
| K9 Security Group Ltd | Administrative & support | 2021 |
| KAF Traffic Limited | Construction | 2024 |
| Kaizah Trading Ltd | Information & communication | 2026 |
| Kalure Ltd | Information & communication | 2025 |
| KAM Cardboard Ltd | Wholesale & retail | 2026 |
| Kamaria Communications Ltd | Information & communication | 2020 |
| Kamway Ltd | Transport & logistics | 2021 |
| Kandore Meat Centre Ltd | Wholesale & retail | 2024 |
| Kanyi Ltd | Construction | 2024 |
| Kaperski Trans Ltd | Transport & logistics | 2013 |
| Karol Mobile Mechanic Ltd | Wholesale & retail | 2026 |
| Kats Eyes Cctv & Alarms Ltd | Manufacturing | 2020 |
| Kausar Takeaway Ltd | Hospitality | 2019 |
| Kayliss Limited | Health & social care | 2022 |
| Kazi Marketing Group Ltd | Professional & scientific | 2018 |
| KCD Kirkhams Custom Designs Ltd | Professional & scientific | 2024 |
| Kdeep Ltd | Wholesale & retail | 2025 |
| KDS Transport Ltd | Transport & logistics | 2016 |
| Keay Properties Limited | Construction | 2020 |
| Kebrell Nuts and Bolts Limited | Wholesale & retail | 1980 |
| Kecc Ltd | Education | 2025 |
| Keith's Kiosk Ltd | Hospitality | 2024 |
| KEL WM Ltd | Construction | 2023 |
| Kelly Christian Design Ltd | Wholesale & retail | 2015 |
| KEM & Reuben Unisex Salon Ltd | Other services | 2025 |
| KEM Hair & Beauty Ltd | Other services | 2026 |
| Kems Barbers Ltd | Other services | 2018 |
| Kemva Holdings Limited | Financial services | 2025 |
| Kenade Resources Limited | Information & communication | 2018 |
| Kenson Limited | Manufacturing | 2000 |
| Kentec Generators Ltd | Manufacturing | 2015 |
| Kepston Holdings Limited | Professional & scientific | 1991 |
| Kepston Limited | Manufacturing | 1923 |
| Kestrel Fields Limited | Hospitality | 2024 |
| Keto High Ltd | Manufacturing | 2018 |
| Keto Internet Sales Ltd | Wholesale & retail | 2023 |
| Keyboard Specialists Ltd | Wholesale & retail | 2006 |
| KEZM3 C.I.C. | Education | 2025 |
| KFB Services (UK) Ltd | Construction | 2024 |
| KFB Services Ltd | Construction | 2016 |
| Khadijatul Kubra Education Centre Ltd | Education | 2025 |
| Khalsa Contractors Ltd | Transport & logistics | 2025 |
| Khalsa Panth Academy Ltd | Information & communication | 2024 |
| Khatana Transport Limited | Transport & logistics | 2020 |
| Khunkhun IT Limited | Information & communication | 2013 |
| Kian Trade Ltd | Wholesale & retail | 2015 |
| Kickstarts Dance C.I.C. | Arts & recreation | 2018 |
| Kienna Ltd | Professional & scientific | 2025 |
| Kindelec Ltd | Construction | 2014 |
| King Edward Street and Pinfold Street Residents Management Limited | Households | 1988 |
| Kingshill Service Centre Limited | Wholesale & retail | 2013 |
| Kingshill Service Station Limited | Wholesale & retail | 2013 |
| Kinnings of Southport Limited | Manufacturing | 1982 |
| Kirbycraft Limited | Real estate | 1997 |
| Kirk Enterprises Ltd | Professional & scientific | 2025 |
| Kitsel Limited | Real estate | 1985 |
| Kitson Testing Ltd | Construction | 2018 |
| KJ Construction Training Ltd | Education | 2018 |
| Klean Energy Ltd | Wholesale & retail | 2026 |
| KLL Accountancy Services Ltd | Professional & scientific | 2022 |
| Klovis Ltd | Wholesale & retail | 2025 |
| KMS Insulations Ltd | Wholesale & retail | 2024 |
| Knighton Legal Services Ltd | Professional & scientific | 2011 |
| KNJ (UK) Property Investments Ltd | Real estate | 2021 |
| Knma Ltd | Information & communication | 2026 |
| KOB Holdings WM Ltd | Real estate | 2025 |
| Kohli M Transport Ltd | Transport & logistics | 2026 |
| Komfort Partitioning Limited | Manufacturing | 2015 |
| Kooner Fleet Management UK Limited | Wholesale & retail | 2025 |
| Kooner Parts Management UK Ltd | Wholesale & retail | 2026 |
| KP Beauty Limited | Other services | 2024 |
| KRD Electrical Limited | Energy | 2002 |
| Kretz & SON Ltd | Manufacturing | 2019 |
| KRG Contractors Limited | Construction | 2002 |