| Klipspringer Limited | Wholesale & retail | 2011 |
| KLM Exterior Cleaning Ltd | Administrative & support | 2026 |
| KLM Ludmila Ltd | Transport & logistics | 2025 |
| KLM Physio Limited | Health & social care | 2026 |
| Klnm Ltd | Hospitality | 2019 |
| KM Plus Ltd | Transport & logistics | 2022 |
| KM Repairs Ltd | Manufacturing | 2019 |
| KMA Forklifts Limited | Manufacturing | 2006 |
| Kmjm HGV Haulage Ltd | Transport & logistics | 2026 |
| KMR Engineering Limited | Manufacturing | 2005 |
| KMS Travel Limited | Administrative & support | 2025 |
| KN Management Limited | Arts & recreation | 2011 |
| Knight Search Ltd | Administrative & support | 2018 |
| Knight Williams Limited | Professional & scientific | 2025 |
| Knighton Consulting Limited | Information & communication | 2000 |
| Knights Integrated Services Limited | Administrative & support | 2023 |
| Knightsdale Ltd | Real estate | 2022 |
| Knightsdale Management Company Limited | Real estate | 2006 |
| Knowing Works CIC | Public administration | 2011 |
| Kobm Limited | Wholesale & retail | 2025 |
| Koca Education Limited | Education | 2025 |
| Kocurek Excavators Limited | Manufacturing | 1982 |
| Kocurek Holdings Limited | Financial services | 2007 |
| KOE Motors Ltd | Administrative & support | 2024 |
| Kofs Shirts Ltd | Wholesale & retail | 2025 |
| Kokopelli Consulting Ltd | Professional & scientific | 2024 |
| KOLLABOR8 Ltd | Professional & scientific | 2017 |
| Kondapatti Limited | Wholesale & retail | 2022 |
| Koni Limited | Real estate | 2015 |
| Kontora Limited | Manufacturing | 2016 |
| Kool Moves Transport Refrigeration Ltd | Manufacturing | 2012 |
| Koolplay Limited | Administrative & support | 2019 |
| Kopano Ltd | Other services | 2025 |
| Korbel Property Company Ltd | Extraterritorial | 2003 |
| Kossymove Ltd | Real estate | 2020 |
| Kostomar Textiles Limited | Wholesale & retail | 2011 |
| Kovan Group Limited | Other services | 2024 |
| Kovi Solution Ltd | Administrative & support | 2025 |
| KP Oral Surgery Services Limited | Health & social care | 2021 |
| KPM Contracts Limited | Construction | 2005 |
| KPW Rail Ltd | Construction | 2014 |
| KR Cakes Ltd | Manufacturing | 2023 |
| KR Ecommerce Ltd | Wholesale & retail | 2025 |
| Kraimoore Homes Ltd | Construction | 2023 |
| KRB Brickwork Ltd | Construction | 2023 |
| Kristian Thomas Limited | Arts & recreation | 2012 |
| Kristinajohn Limited | Administrative & support | 2016 |
| Krivernik Transport Ltd | Transport & logistics | 2020 |
| Krocus Limited | Information & communication | 2016 |
| KRS PVT Ltd | Wholesale & retail | 2025 |
| KRT Associates Limited | Professional & scientific | 2017 |
| Krustys Limited | Manufacturing | 2003 |
| KS (AO) Ltd | Wholesale & retail | 2012 |
| KS Auto Solutions Ltd | Wholesale & retail | 2024 |
| KS Safe Places Ltd | Real estate | 2025 |
| KS Sports Management Limited | Arts & recreation | 2023 |
| Kshouse SPV Ltd | Real estate | 2025 |
| KSJ Properties Limited | Real estate | 2019 |
| KSS Ipswich Ltd | Wholesale & retail | 2020 |
| KSS Properties Ipswich Ltd | Real estate | 2023 |
| KSY Women's Health Ltd | Education | 2026 |
| Ktec Limited | Professional & scientific | 2004 |
| KTN Motors Ltd | Wholesale & retail | 2022 |
| Kubernesis Ltd | Professional & scientific | 2022 |
| Kuda (U.K.) Ltd. | Manufacturing | 1991 |
| Kuda Accessories Limited | Wholesale & retail | 2012 |
| Kuda Properties Limited | Real estate | 2012 |
| Kurdo 47 Ltd | Hospitality | 2015 |
| Kurtis Engineering Ltd | Professional & scientific | 2025 |
| Kurum Ltd | Hospitality | 2021 |
| KUS Kebab Ltd | Hospitality | 2025 |
| Kutivz Business Services Ltd | Hospitality | 2019 |
| Kutivz Kollection Limited | Wholesale & retail | 2023 |
| KVS Food & Wine Ltd | Other services | 2014 |
| KW Holdings Limited | Financial services | 2005 |
| Kwiboo Ltd | Information & communication | 2007 |
| Kwik Trans Ltd | Transport & logistics | 2020 |
| KWL (Felixstowe) Limited | Financial services | 2016 |
| Kyara Beauty and Hair Salon Ltd | Other services | 2020 |
| Kybeleconsult Limited | Information & communication | 2023 |
| Kyson Developments Ltd | Construction | 1997 |
| KZ Bite Ltd | Hospitality | 2024 |
| KZP Smart Transport Ltd | Transport & logistics | 2023 |
| L & E Rotating Electrics Ltd | Wholesale & retail | 2021 |
| L & H Vehicle Services Limited | Manufacturing | 2002 |
| L & J Driver Hire Limited | Transport & logistics | 2023 |
| L & R Contractors Limited | Administrative & support | 2003 |
| L & T Investments Ltd | Professional & scientific | 2014 |
| L and a Commercial Limited | Construction | 2019 |
| L Deacon Heating Ltd | Construction | 2022 |
| L J Baalham Transport Limited | Transport & logistics | 2013 |
| L J Phillips Agencies Ltd | Transport & logistics | 2025 |
| L J S Arthey & Sons Limited | Agriculture & fishing | 2022 |
| L L M R Property Ltd | Hospitality | 2025 |
| L Price Enterprises Limited | Arts & recreation | 2022 |
| L S Scissors Ltd | Other services | 2022 |
| L W Supplies Ltd | Wholesale & retail | 2025 |
| L Y Ipswich Ltd | Wholesale & retail | 2019 |
| L&L Assets Ltd | Real estate | 2020 |
| L&T Strategic Finance Advisor Ltd | Transport & logistics | 2015 |