| JSC Lydon Holdings Limited | Financial services | 2018 |
| Just-Beauty-Touch Ltd | Wholesale & retail | 2014 |
| K Yummy Limited | Hospitality | 2023 |
| K. ORD Paving & Groundworks Limited | Construction | 2006 |
| Kaan Barbers Ltd | Other services | 2026 |
| Karrs Transport Ltd | Transport & logistics | 2018 |
| Kaur PA Services Ltd | Administrative & support | 2016 |
| KD Software Solutions Limited | Information & communication | 2025 |
| KDM Estates Limited | Real estate | 2007 |
| Kebab Express PN Ltd | Wholesale & retail | 2020 |
| Keraleeyam Ltd | Hospitality | 2024 |
| Keystone Energy Partners Limited | Energy | 2025 |
| Khalsa Enterprises Limited | Hospitality | 2016 |
| KJR Mechanical Engineering Ltd | Professional & scientific | 2024 |
| KNA Convenience Store Ltd | Wholesale & retail | 2023 |
| Knock Your Socks OFF by Rebeca Ltd | Health & social care | 2025 |
| Kookaburra Holdings Limited | Financial services | 2026 |
| KP Healthcare Limited | Health & social care | 2026 |
| Krystal Cleaning Services Limited | Administrative & support | 2003 |
| Kt&T Brothers Ltd | Real estate | 2026 |
| KW Jointing NE Limited | Construction | 2026 |
| Kxylss Ltd | Transport & logistics | 2026 |
| Kyrast Zorvyn Limited | Wholesale & retail | 2026 |
| L W 76 Ltd | Hospitality | 2025 |
| Laid & Slayed Ltd | Other services | 2025 |
| Lamont Martelle Limited | Real estate | 2011 |
| Landtime Limited | Real estate | 1999 |
| Lauren-Elizabeth Aesthetics Ltd | Other services | 2020 |
| Lbkh Limited | Professional & scientific | 2014 |
| LE5 Services Ltd | Professional & scientific | 2013 |
| Learning Abilities CIC | Public administration | 2023 |
| LEC Consultancy Limited | Professional & scientific | 2014 |
| LEE Black Foundation CIC | Health & social care | 2023 |
| LEE Wright Property Services Ltd | Households | 2021 |
| Leef Services Limited | Manufacturing | 2020 |
| Leesi Electrical Ltd | Construction | 2025 |
| LG Physiotherapy Limited | Health & social care | 2014 |
| Liam TR Traffic Management Ltd | Construction | 2017 |
| Life Support Pizza Ltd | Hospitality | 2025 |
| Lift Maintenance Limited | Manufacturing | 2023 |
| Light Without Limits Ltd | Administrative & support | 2025 |
| Lion Removals Ltd | Transport & logistics | 2025 |
| Lister Leasing Limited | Real estate | 2026 |
| LLE Mechanical Limited | Construction | 2023 |
| LLP Aesthetics & Beauty Limited | Other services | 2024 |
| LLP Services Limited | Wholesale & retail | 2023 |
| LLR Wind Ltd | Construction | 2025 |
| LM by Food Centre Ltd | Wholesale & retail | 2004 |
| Lokman Training Ltd | Professional & scientific | 2012 |
| London Bar & Kitchen Limited | Wholesale & retail | 2004 |
| Lorimers Consultancy Limited | Health & social care | 2015 |
| Love 4D Love Ltd | Real estate | 2022 |
| Love Life Events Limited | Arts & recreation | 2026 |
| LTW Offshore Hvac Services Limited | Professional & scientific | 2023 |
| Lumina Retreats Ltd | Real estate | 2026 |
| Lynto Global Limited | Administrative & support | 2025 |
| Lynx Studios Ltd | Information & communication | 2024 |
| M and G Local Ltd | Wholesale & retail | 2019 |
| M & R Publishing Ltd | Information & communication | 2019 |
| M&E Ceausescu Limited | Transport & logistics | 2021 |
| M. F. Sulkowski Construction Ltd | Construction | 2024 |
| M.A.C.'s Electrical Services Limited | Construction | 2016 |
| MAC HAS Power Ltd | Information & communication | 2026 |
| Mamma Social Foundation Community Interest Company | Other services | 2022 |
| Marian Toscuta Ltd | Transport & logistics | 2025 |
| Mark Antony Kirkup Ltd | Extraterritorial | 2024 |
| Marmaris Easington Barber Shop Limited | Other services | 2026 |
| Mash Electrical Ltd | Construction | 2022 |
| MAT Jumper Transport Ltd | Transport & logistics | 2019 |
| MAW Engineering 1978 Limited | Manufacturing | 2019 |
| Mcarsonly Limited | Wholesale & retail | 2025 |
| MCF Plus+ Limited | Administrative & support | 2019 |
| Mend My Window Limited | Construction | 2018 |
| MIF Moko Limited | Wholesale & retail | 2025 |
| Mine NOW Ltd | Wholesale & retail | 2025 |
| Minefield Property Ltd | Construction | 2025 |
| MIS Coatings Limited | Construction | 2016 |
| MIS North East Limited | Transport & logistics | 2010 |
| Misschiefchaos Limited | Wholesale & retail | 2025 |
| MKG Protection & Security Services Ltd | Administrative & support | 2021 |
| MLB Groundworkers Limited | Construction | 2025 |
| MMF Groundworks Services Ltd | Construction | 2024 |
| MML Consultants Ltd | Information & communication | 2026 |
| Momo Longing Limited | Wholesale & retail | 2025 |
| Moonb Ltd | Wholesale & retail | 2026 |
| Moscis Ltd | Wholesale & retail | 2022 |
| Msmundi Ltd | Hospitality | 2025 |
| Mupedziswa Medical Ltd | Health & social care | 2009 |
| MW Plumbing Services Ltd | Construction | 2020 |
| MW Property and Hospitality Limited | Hospitality | 2022 |
| MYHAI2002 Limited | Transport & logistics | 2016 |
| Myrkyn Liorth Limited | Wholesale & retail | 2026 |
| N & S Hartnack Limited | Wholesale & retail | 2017 |
| N Supps Ltd | Manufacturing | 2023 |
| N&P Construction Services Ltd | Construction | 2026 |
| Nathan's Creator Agencies Ltd | Information & communication | 2024 |
| NDT Supplies Limited | Extraterritorial | 2016 |
| NE 1 Accountants Ltd | Professional & scientific | 2018 |
| New Eden Fish Inn Ltd | Hospitality | 2025 |
| New YOU Facial Aesthetics Ltd | Administrative & support | 2018 |