| K O Carpentry Limited | Construction | 2007 |
| K Parrish & SON Ltd | Real estate | 2021 |
| K.P Stone Ltd | Manufacturing | 2024 |
| KAI Sheng International Limited | Water & waste | 2015 |
| Kairo Care Ltd | Health & social care | 2026 |
| Kaizen Technology Ltd | Manufacturing | 2002 |
| Kamil Coaching Ltd | Education | 2025 |
| Kantilever Limited | Information & communication | 2016 |
| Kanyi King LLP | | 2013 |
| Katie’S Kundalini Crystals Limited | Wholesale & retail | 2021 |
| Katrine Kielos Limited | Information & communication | 2013 |
| Kauri Productions Limited | Administrative & support | 2009 |
| KBS Consulting Limited | Administrative & support | 2022 |
| KD Associates Limited | Administrative & support | 2015 |
| KD Land Planning Development Limited | Construction | 2018 |
| Keezark Ltd | Hospitality | 2019 |
| Kellythorn Consultancy Services Ltd | Construction | 2006 |
| Kelly’S Cake Kitchen Bakery Limited | Manufacturing | 2023 |
| Kelly’S Cake Kitchen Limited | Wholesale & retail | 2021 |
| Kelshall Contracting Limited | Agriculture & fishing | 1998 |
| Kelshall Plot 1 Limited | Construction | 2024 |
| Kempston Properties Ltd | Real estate | 1998 |
| Kemptown | Financial services | 2020 |
| Kennedy House Consulting Ltd | Professional & scientific | 2008 |
| Ketts & ETC Limited | Information & communication | 2012 |
| Key Points Limited | Professional & scientific | 1989 |
| Keypoints Europe Limited | Professional & scientific | 2000 |
| Kick the Plug Ltd | Information & communication | 2012 |
| Kids Travel Packs Limited | Manufacturing | 2026 |
| KIM Whitaker Legal Services Limited | Professional & scientific | 2018 |
| King James Way Flat Management Ltd | Households | 2025 |
| Kingston Pastures Management Ltd | Households | 2026 |
| Kingsway Golf Centres Limited | Arts & recreation | 2005 |
| Kingsway Golf Limited | Arts & recreation | 2024 |
| Kinlochlaich Treehouse Ltd | Hospitality | 2015 |
| KIO POD Ltd | Manufacturing | 2024 |
| Kirkwood Structures Limited | Professional & scientific | 2018 |
| Kiss Brands Limited | Wholesale & retail | 2024 |
| Kitcheners Lane Ltd | Real estate | 2019 |
| Kitchens Limited | Construction | 1969 |
| Kneesworth Farms Holdings Limited | Financial services | 2024 |
| Koggno Ltd | Health & social care | 2021 |
| KOH Branded Limited | Wholesale & retail | 2008 |
| Kokoro Media Limited | Professional & scientific | 2020 |
| Kokoro Performance Limited | Professional & scientific | 2013 |
| Kooky Nohmad Go Ltd | Hospitality | 2025 |
| Kooky Nohmad Group Limited | Financial services | 2020 |
| Kooky Nohmad Royston Limited | Other services | 2020 |
| Korda Medical Consulting Limited | Administrative & support | 2025 |
| KP Creative Consulting Limited | Professional & scientific | 2021 |
| KPC Building Services Limited | Construction | 2013 |
| Krafty Creators Limited | Wholesale & retail | 2022 |
| KTM Property Services Ltd | Real estate | 2023 |
| KTT Pure Ltd | Households | 2013 |
| Kuche UK Ltd. | Professional & scientific | 2008 |
| KWS UK Limited | Agriculture & fishing | 1981 |
| Kyne Ltd | Manufacturing | 2021 |
| L & a Connect Limited | Wholesale & retail | 2015 |
| L & H Carpentry Ltd | Construction | 2007 |
| L a Associates Ltd | Construction | 2019 |
| L J M Properties Limited | Real estate | 2016 |
| L.A. Painting and Decorating Limited | Construction | 2020 |
| LA Bella Vita (Royston) Ltd | Wholesale & retail | 2022 |
| LA Caza Properties Ltd | Hospitality | 2023 |
| LA Loupe Court Management Company Limited | Households | 2017 |
| Labyrinth Scenics Limited | Construction | 2021 |
| Lakam Ltd | Arts & recreation | 2019 |
| Lakeside Deliveries Limited | Administrative & support | 2006 |
| Lambert Constructions (Cambridge) Limited | Construction | 1967 |
| Landbeach Estates Limited | Households | 2000 |
| Landieman Media Consulting Limited | Professional & scientific | 2016 |
| Landlords Compliance Services Ltd | Professional & scientific | 2026 |
| Landmark Restoration Limited | Construction | 2003 |
| Landsgate Investments Limited | Professional & scientific | 2007 |
| Lane Farm Limited | Agriculture & fishing | 2012 |
| Lane Management Limited | Households | 2000 |
| Lanevo Estates Ltd | Real estate | 2022 |
| Lantern Health and Safety Management Solutions Limited | Professional & scientific | 2022 |
| Laura B Health Care Limited | Health & social care | 2022 |
| Laurel Developments & Consulting Limited | Real estate | 2014 |
| Laurie Mansworth Productions Ltd | Arts & recreation | 2011 |
| Laurie Mansworth Publishing Ltd | Information & communication | 2011 |
| Laurient Ltd | Real estate | 2020 |
| Law Farms Ltd | Agriculture & fishing | 2008 |
| Lawson and Green Ltd | Professional & scientific | 1986 |
| Layston Construction Ltd | Construction | 2012 |
| Lazos Grove Limited | Wholesale & retail | 2023 |
| Lbke Properties Limited | Real estate | 2023 |
| LCE Construction Services Ltd | Construction | 2024 |
| LCW Business Support Services Ltd | Administrative & support | 2024 |
| LD & C Homes Ltd | Extraterritorial | 2026 |
| LD & C Ltd | Extraterritorial | 2024 |
| LDC1 Limited | Real estate | 2020 |
| LDC2 Limited | Real estate | 2023 |
| Ldgs Cambs Ltd | Real estate | 2015 |
| LDS Test Technologies Limited | Manufacturing | 2026 |
| LE Blond Ltd | Manufacturing | 2024 |
| Leaden Hill Residents Committee Ltd | Households | 2025 |
| Leading Leaders Limited | Professional & scientific | 2007 |
| Ledgerxp Ltd | Professional & scientific | 2026 |