| K & M Allison Ltd | Extraterritorial | 2024 |
| K & M Properties (KL) Limited | Real estate | 2017 |
| K a Agricultural Machinery Importers Limited | Wholesale & retail | 2012 |
| K Brown Auto Repairs (KL) Ltd | Manufacturing | 2012 |
| K Brown Auto Repairs (Property) Ltd | Real estate | 2026 |
| K Brown Auto Repairs Ltd | Wholesale & retail | 2003 |
| K C Sustainability Limited | Professional & scientific | 2025 |
| K L MOT Centre Limited | Wholesale & retail | 2024 |
| K L Nuts Bolts and Engineering Supplies Ltd | Wholesale & retail | 2011 |
| K L Ringer Building and Groundworks Limited | Administrative & support | 2017 |
| K M Fine Design Limited | Construction | 2007 |
| K Martin & SON EOT Limited | Administrative & support | 2023 |
| K V T Business Care Limited | Professional & scientific | 2013 |
| K White Site Services Limited | Construction | 2014 |
| K&C Projects Ltd | Construction | 2023 |
| K&D Cleaning Services Ltd | Administrative & support | 2017 |
| K&S Property Services Ltd | Households | 2023 |
| K-Omics Ltd | Professional & scientific | 2024 |
| K.L. Engine Centre Limited | Wholesale & retail | 1992 |
| Kaitain Ltd | Administrative & support | 2017 |
| Kaizen Coaching Ltd | Health & social care | 2023 |
| Kakapo Arts Ltd | Arts & recreation | 2020 |
| Kallepuram Investments Ltd | Real estate | 2022 |
| Kalsky Investments Limited | Real estate | 2021 |
| Kanolty Holdings Limited | Professional & scientific | 1991 |
| Kantalogistic Limited | Transport & logistics | 2018 |
| Karanlikdere Ltd | Hospitality | 2026 |
| KARE&KOM4T Limited | Real estate | 2022 |
| Karekare Productions Ltd | Arts & recreation | 2023 |
| Karl Tordoff Limited | Construction | 2017 |
| Katie Temple Ltd | Administrative & support | 2016 |
| Kayak Services Ltd | Manufacturing | 2022 |
| Kbioservices Limited | Manufacturing | 1999 |
| Kbiosystems Limited | Manufacturing | 1989 |
| KC 2000 Ltd | Wholesale & retail | 2000 |
| KCY Metal & Waste Management Limited | Water & waste | 2024 |
| KD Financial Solution Ltd | Professional & scientific | 2025 |
| KDH Training and Assessment Ltd | Education | 2022 |
| KE LIN Mandarin Limited | Professional & scientific | 2023 |
| KE52TIS Ltd | Transport & logistics | 2014 |
| Keith Hanson Road Transport Ltd | Transport & logistics | 2003 |
| Keith Sandle Limited | Information & communication | 2010 |
| Kellmatt Barbers Ltd | Other services | 2025 |
| Kellys Scaffolding Limited | Construction | 2015 |
| Kellyvision (KCS) Limited | Wholesale & retail | 2000 |
| Kempton Park Farm Dog Day Care Limited | Other services | 2025 |
| Kennedy Lewis Consulting Limited | Administrative & support | 2020 |
| Kenneth Bush Ltd | Professional & scientific | 2013 |
| Kenwick Hall Gardens Management Limited | Professional & scientific | 2001 |
| Kerala Kalavara Ltd | Hospitality | 2024 |
| Kerridge Court Management Company Limited | Households | 1989 |
| Kerrkady & Sons Ltd | Construction | 2023 |
| Kesu (UK) Limited | Real estate | 2009 |
| Kevin Salter Developments Limited | Construction | 2000 |
| Key LET Living Ltd | Real estate | 2025 |
| Keyzero Consulting Ltd | Information & communication | 2016 |
| KGL Pubs Ltd | Hospitality | 2025 |
| Khellon Services Ltd | Health & social care | 2024 |
| Khoowala Trader Limited | Wholesale & retail | 2025 |
| Kieran Mayes Brickworks Limited | Construction | 2026 |
| Kiessan Limited | Real estate | 2011 |
| Kiev Coffee Ltd | Wholesale & retail | 2025 |
| King Electrical Solutions Ltd | Construction | 2025 |
| King's Butchers Limited | Manufacturing | 2018 |
| King's Lynn Aero Modelling Club Ltd. | Arts & recreation | 2015 |
| King's Lynn BID Limited | Other services | 2017 |
| King's Lynn Camping and Caravan Park Limited | Hospitality | 2012 |
| King's Lynn Child Contact Centre C.I.C. | Other services | 2012 |
| King's Lynn Chiropractic Clinic Ltd | Health & social care | 2006 |
| King's Lynn Construction Ltd | Construction | 2018 |
| King's Lynn Developments Limited | Construction | 2023 |
| King's Lynn Electrical Engineering Ltd | Construction | 2007 |
| King's Lynn Festival Limited | Arts & recreation | 1997 |
| King's Lynn Football Club Ltd | Arts & recreation | 2009 |
| King's Lynn KOI Limited | Wholesale & retail | 2003 |
| King's Lynn Masonic Centre Limited | Real estate | 2003 |
| King's Lynn Notary Services Ltd | Professional & scientific | 2024 |
| King's Lynn Roofing Ltd | Construction | 2019 |
| King's Lynn School of Motoring Ltd | Education | 2016 |
| King's Lynn Taxis Limited | Extraterritorial | 2002 |
| King's Lynn Town Football Club Ltd | Arts & recreation | 2010 |
| King's Lynn Website Design Ltd | Information & communication | 2011 |
| Kingfisher Project Developments Ltd | Construction | 1999 |
| Kings Court (Sheringham) Management Company Limited | Real estate | 2009 |
| Kings Lynn and District Motor Club Limited | Arts & recreation | 1984 |
| Kings Lynn Angling Association Limited | Agriculture & fishing | 2013 |
| Kings Lynn Caravan and Camping Park Limited | Hospitality | 2003 |
| Kings Lynn IT Support Ltd | Information & communication | 2012 |
| Kings Lynn Mobility Centre Ltd. | Wholesale & retail | 2003 |
| Kings Lynn Oval Racing Limited | Arts & recreation | 2010 |
| Kings Lynn Venues Ltd | Hospitality | 2025 |
| Kings Lynn Warehousing and Distribution Limited | Transport & logistics | 1970 |
| Kingswear Coffee Company Limited | Hospitality | 2017 |
| Kinsley Store Ltd | Wholesale & retail | 2022 |
| Kirk Plant Ltd | Hospitality | 2024 |
| Kissd Ltd | Manufacturing | 2021 |
| Kittana UK Ltd | Wholesale & retail | 2023 |
| Kizhakkethil Enterprises Limited | Health & social care | 2023 |
| KJ Sheds and Timber Ltd | Wholesale & retail | 2020 |
| Kkad Ltd | Professional & scientific | 2017 |