| KHB Consult Ltd | Information & communication | 2023 |
| Kidlington Cafe Ltd | Hospitality | 2025 |
| Kidlington Childcare Limited | Education | 2021 |
| Kidlington China Delight Limited | Hospitality | 2024 |
| Kidlington Fencing (Oxford) Ltd | Administrative & support | 2021 |
| Kidlington Tyre & Auto Centre Ltd | Wholesale & retail | 2022 |
| Kinesiox Ltd | Wholesale & retail | 2024 |
| Kinetic Business Solutions UK Limited | Administrative & support | 2025 |
| KING8TRIX Ltd | Construction | 2026 |
| Kingerlee Holdings Limited | Real estate | 1970 |
| Kingerlee Homes Limited | Real estate | 2008 |
| Kingerlee Limited | Construction | 1980 |
| Kingham Aviation Ltd | Transport & logistics | 2019 |
| Kings Two Wheel Centre Ltd. | Wholesale & retail | 2003 |
| Kingsmead Management Company (Loudwater) Limited | Administrative & support | 1989 |
| Kingsway Securities Limited | Real estate | 1998 |
| Kirtlington Park Limited | Other services | 2008 |
| Kirtlington Park Management Limited | Administrative & support | 2018 |
| Kirtlington Projects Limited | Real estate | 2017 |
| Kirtlington Property Services Ltd | Manufacturing | 2025 |
| Kirtlington Stud Limited | Agriculture & fishing | 1964 |
| KJ Cleaning Solutions Ltd | Administrative & support | 2020 |
| KK Pest Control Ltd | Professional & scientific | 2025 |
| KLK Consult Limited | Professional & scientific | 2025 |
| Knight Carpet & Flooring Limited | Construction | 2023 |
| Knoxed Capital Limited | Financial services | 2024 |
| Knoxed Limited | Manufacturing | 2004 |
| Kraken Holdings Ltd | Real estate | 2015 |
| Krishnivas Investment Ltd | Real estate | 2023 |
| KSK K9 Security Ltd | Administrative & support | 2019 |
| Kuok Jian Foong Ltd | Other services | 2024 |
| L J Nails & Beauty Limited | Other services | 2018 |
| L.P.G Composites Ltd | Manufacturing | 2025 |
| Ladygrove Court (Abingdon) Management Company Limited | Households | 2001 |
| Lambert Property Portfolio Limited | Real estate | 2019 |
| Landauer Europe, Ltd. | Professional & scientific | 2002 |
| Landauer, Inc. | | 1992 |
| Langford Locks Management Limited | Real estate | 1999 |
| Lantern Care Homes Ltd | Health & social care | 2019 |
| Law Reports International Limited | Information & communication | 2011 |
| Lawn Upton Management Limited | Households | 2014 |
| Lawrence Technical Services Ltd | Professional & scientific | 2016 |
| LCF Tiles Limited | Construction | 2023 |
| LCP Associates Limited | Professional & scientific | 2012 |
| Leading Edge Aviation Ltd | Education | 2018 |
| Levare Dental Agency Ltd | Administrative & support | 2020 |
| Libby Heaney Studio Ltd | Arts & recreation | 2023 |
| Lifely Forbes Limited | Financial services | 2026 |
| Liftd Design Global Ltd | Professional & scientific | 2022 |
| Liftd Design Ltd | Professional & scientific | 2020 |
| Lime Walk Capital Limited | Manufacturing | 2024 |
| Lincombe Lodge Management Company Limited | Households | 2007 |
| Liquid Script Limited | Professional & scientific | 2025 |
| Little Dene Management Company Limited | Households | 2017 |
| Little Orchard View (Poole) Management Company Limited | Households | 2021 |
| Little Oxford (NO.2) Management Company Limited | Households | 1993 |
| Little Oxford (NO.4) Management Company Limited | Households | 1993 |
| Live Life Personalised Ltd | Manufacturing | 2023 |
| Lizmans Court Freehold Limited | Households | 2012 |
| Lizmans Court Management Company Limited | Households | 2003 |
| LKB Properties Consultancy Limited | Real estate | 2010 |
| Llifwyr Limited | Manufacturing | 2008 |
| LMN Bookkeeping Plus Ltd | Professional & scientific | 2021 |
| Local Cars Oxford Ltd | Transport & logistics | 2022 |
| Lodge Hill Garage Limited | Wholesale & retail | 2003 |
| Logistics Optimisation Consultants Ltd | Information & communication | 2024 |
| London Construction 22 Ltd | Construction | 2021 |
| Lord Consultants Limited | Professional & scientific | 2006 |
| Loro Management Limited | Professional & scientific | 2010 |
| Louie Paine Limited | Construction | 2006 |
| Loxwood Aviation Limited | Transport & logistics | 2012 |
| Loxwood Holdings Limited | Construction | 2007 |
| LSJ Economics Ltd | Professional & scientific | 2023 |
| Lucas Accountancy Limited | Professional & scientific | 2003 |
| Lucy Eaton Productions Ltd | Information & communication | 2024 |
| LUK YEE Garden Limited | Real estate | 2020 |
| Lula's Ethiopian Cuisine Restaurant Ltd | Hospitality | 2025 |
| Luwigolds Limited | Administrative & support | 2014 |
| Luxett Ltd | Transport & logistics | 2023 |
| Luxuryxarr Ltd | Wholesale & retail | 2023 |
| LVS Aero Limited | Transport & logistics | 2013 |
| Lyne House Limited | Hospitality | 2013 |
| M & C Paving Limited | Construction | 2006 |
| M & C Roofing and Building Ltd | Construction | 2024 |
| M & D Properties (Oxford) Limited | Real estate | 1998 |
| M F Couriers Limited | Transport & logistics | 1986 |
| M H Energy Consultants Limited | Other services | 2007 |
| M NAJ Electrical Ltd | Construction | 2025 |
| M Rudge Tree Services Limited | Agriculture & fishing | 2012 |
| M V Firmin Garden Landscaping Limited | Administrative & support | 2021 |
| M&A Formwork Ltd. | Construction | 2013 |
| M&J Estate Agent Ltd | Real estate | 2024 |
| M. H. Parsons Renovations Ltd | Construction | 1998 |
| M2 Motor Group Limited | Wholesale & retail | 2025 |
| MAC Repair Oxford Limited | Other services | 2022 |
| Macedonian Harmony Limited | Arts & recreation | 2026 |
| Macfaction Ltd | Information & communication | 2017 |
| Macwilliam Media Projects Ltd | Extraterritorial | 2016 |
| Madden Holdings Limited | Financial services | 2022 |
| Maego Consulting Limited | Professional & scientific | 2016 |