| Kevin Feighery Counselling and Consultancy Ltd | Health & social care | 2016 |
| Kevin Stott Racing Ltd | Arts & recreation | 2023 |
| Keyde Advisory Ltd | Professional & scientific | 2025 |
| Keystone Osteopathy Limited | Health & social care | 2010 |
| KFP Holdings Limited | Information & communication | 2024 |
| KFP Total IT Solutions Ltd | Information & communication | 2013 |
| KGB Cleaning South West EOT Ltd | Administrative & support | 2025 |
| KGB Cleaning South West Limited | Administrative & support | 2009 |
| KGL Studio Labs Ltd | Information & communication | 2025 |
| Kharbury Roth Limited | Professional & scientific | 2023 |
| Kieran Shoemark Racing Ltd | Arts & recreation | 2020 |
| Kilgannon Communications Limited | Professional & scientific | 2017 |
| Killian Property Investments Limited | Real estate | 2019 |
| Kimyo Limited | Information & communication | 2024 |
| Kinder Fluff UK Ltd | Wholesale & retail | 2019 |
| Kingdom Signs Limited | Professional & scientific | 2018 |
| Kingfisher Property Developments Limited | Construction | 2011 |
| Kingsmead Game Services Limited | Agriculture & fishing | 2020 |
| Kingston Bagpuize House Events Limited | Arts & recreation | 2008 |
| Kingston Bagpuize Sportsfield Limited | Professional & scientific | 2023 |
| Kinia Innovations Ltd | Wholesale & retail | 2025 |
| Kinowork Productions Ltd | Arts & recreation | 2015 |
| Kioxia Technology UK Ltd | Professional & scientific | 2011 |
| Kiril Trans Ltd | Manufacturing | 2026 |
| KJ Plus Architects Ltd | Professional & scientific | 2016 |
| Klaxton Capital Ltd | Financial services | 2024 |
| Klout Twenty Three Limited | Professional & scientific | 2019 |
| KM Beauty Limited | Other services | 2015 |
| Kobo Products Ltd | Wholesale & retail | 2018 |
| Kolo Social Ltd | Information & communication | 2025 |
| Kommunikate Ltd | Professional & scientific | 2019 |
| Kona Associates Limited | Administrative & support | 2011 |
| Konect Resources Limited | Information & communication | 2010 |
| Kormocha PVT Ltd | Real estate | 2025 |
| Kosstom Ltd | Wholesale & retail | 2021 |
| Koven Limited | Arts & recreation | 2021 |
| Koven Touring LLP | | 2021 |
| KP Construction (Oxford) Limited | Construction | 2018 |
| Kreative Imports Ltd | Wholesale & retail | 2023 |
| Krzysztof Contractors Ltd | Administrative & support | 2017 |
| KS Electricity Limited | Manufacturing | 2026 |
| KSR Consulting Ltd | Information & communication | 2019 |
| Ktbg Music Ltd | Information & communication | 2022 |
| Kult Management Limited | Arts & recreation | 2008 |
| KWC Heating Services Limited | Construction | 2016 |
| L & L Trading House Limited | Administrative & support | 2012 |
| L a Group Oxford Limited | Construction | 2017 |
| L J Accountancy Ltd | Professional & scientific | 2017 |
| L Myers Building Services Ltd | Construction | 2017 |
| L&D Design and Installation Limited | Construction | 2023 |
| L.I.D. Property Limited | Real estate | 2017 |
| LA Carers Ltd | Health & social care | 2020 |
| Labequip Ltd | Manufacturing | 2023 |
| Laces Music Ltd | Arts & recreation | 2024 |
| LAH Holdings Limited | Real estate | 2024 |
| Lainet Psychology Ltd | Education | 2025 |
| Lakshay Investments Group Limited | Hospitality | 2022 |
| LAM Transport Ltd | Transport & logistics | 2023 |
| Lambourn Bennett Ltd | Real estate | 2018 |
| Lamol Consultancy Ltd | Construction | 2024 |
| Land & Property Terrier Ltd | Public administration | 2021 |
| Land Consultants Ltd | Real estate | 2024 |
| Lantic Holdings Ltd | Financial services | 2025 |
| Laraalexis Limited | Education | 2016 |
| Larkhill Management Company Limited | Households | 1993 |
| Larkhill Professional Services Ltd | Administrative & support | 2013 |
| Lascaux Pharmaceuticals Limited | Health & social care | 1996 |
| Laser TAG in a Box Ltd | Arts & recreation | 2013 |
| Laughta Music Limited | Arts & recreation | 2023 |
| Laura Louise London Ltd | Information & communication | 2025 |
| Laurence Raasch Poultry Ltd | Agriculture & fishing | 2015 |
| Lavender Assets Management Ltd | Transport & logistics | 2012 |
| Law and Property Lawyers Limited | Real estate | 2010 |
| Laxmi Logic Limited | Information & communication | 2016 |
| Lazare Property Management Services Limited | Real estate | 2015 |
| LB Touring Limited | Arts & recreation | 2017 |
| LCR Property Ltd | Real estate | 2023 |
| LCT Support Services Ltd | Transport & logistics | 2003 |
| LE Fevre Consulting Limited | Professional & scientific | 2003 |
| LE Mans Fine Art Ltd | Wholesale & retail | 2023 |
| LE Mans Motorsport Gallery Ltd | Wholesale & retail | 2023 |
| LEA Park (V) North Limited | Extraterritorial | 1976 |
| LEA Park (V) South Limited | Extraterritorial | 1976 |
| LEA Park Management (East) Company Limited | Households | 1974 |
| LEA Park Management (West) Company Limited | Extraterritorial | 1974 |
| Leaf Mobility Ltd | Transport & logistics | 2026 |
| Leafe Property Limited | Real estate | 2023 |
| Leapmind Ltd | Information & communication | 2022 |
| Learn With Cognitive Analytic Therapy Oxfordshire Ltd | Professional & scientific | 2022 |
| LEE Garage Abingdon Ltd | Wholesale & retail | 2022 |
| Leicester Global Study Centre Limited | Education | 2018 |
| Leichauer Engineering Ltd | Professional & scientific | 2022 |
| Leirasoft Limited | Information & communication | 2019 |
| Leisure Direction Travel Limited | Administrative & support | 2008 |
| LEM Main Supply Ltd | Wholesale & retail | 2026 |
| LEMKA2 Ltd | Information & communication | 2024 |
| Lemore Property Limited | Real estate | 2025 |
| LEO Fibre and Network Cabling Ltd | Construction | 2021 |
| Let's Hope SO Ltd | Hospitality | 2023 |
| Letsmove Oxfordshire Ltd | Information & communication | 2011 |