| Grey Stripe Consulting Limited | Professional & scientific | 2024 |
| Griftec Ltd | Administrative & support | 2019 |
| Grim Fabrications Ltd | Information & communication | 2023 |
| Grosvenor Park (Mill Hill) Management Company Limited | Households | 2006 |
| GSP SET Decorating Ltd | Arts & recreation | 2024 |
| Gtae Services Ltd | Information & communication | 2021 |
| Gumboots Limited | Professional & scientific | 2022 |
| Gutter Cleaning & Drainage Solutions Ltd | Water & waste | 2023 |
| GVG Studio Services Ltd | Information & communication | 2015 |
| Gwendoline Court Management Company Limited | Administrative & support | 2007 |
| H2O Power Towy Ltd | Energy | 2013 |
| H8MUD Limited | Professional & scientific | 2024 |
| HAK Business Solutions Limited | Administrative & support | 2015 |
| Hammer FOX Limited | Construction | 2015 |
| Hdsets Ltd | Manufacturing | 2025 |
| Herts and Homes Developments Ltd | Construction | 2026 |
| HIO Holdings Ltd | Financial services | 2025 |
| Hoirlan Limited | Transport & logistics | 2025 |
| Home and Property Solutions Ltd | Real estate | 2022 |
| Home Sweet Home Property Services Ltd | Real estate | 2022 |
| Homecare Plumbers Limited | Construction | 2021 |
| Homewood SFX Limited | Arts & recreation | 2018 |
| Hot & Bothered Ltd | Information & communication | 2021 |
| Hotset Plastering Services Limited | Other services | 2013 |
| House Bonitas Ltd | Real estate | 2024 |
| I and P Consulting Limited | Professional & scientific | 2018 |
| I Babar Medical Services Ltd | Health & social care | 2023 |
| Iberian Engineering Services Ltd | Professional & scientific | 2022 |
| Imedicare Limited | Wholesale & retail | 2004 |
| IN the Loop Systems Limited | Information & communication | 2016 |
| IN Treatment London Ltd | Professional & scientific | 2022 |
| Innerview Limited | Professional & scientific | 2003 |
| Intelrail Ltd | Construction | 2021 |
| Iron Bubble Carpentry Joinery Ltd | Information & communication | 2023 |
| Iron Films Ltd | Information & communication | 2023 |
| Ironwood Developments Ltd | Real estate | 2026 |
| Irwell Hydro Limited | Financial services | 2019 |
| J G K Limited | Information & communication | 2009 |
| J Preston Builders Limited | Construction | 2013 |
| J T Roberts Scenic Services Ltd | Information & communication | 2011 |
| J3 Property Group Ltd | Real estate | 2024 |
| Jack Hillyer Carpentry Limited | Manufacturing | 2022 |
| Janes Consortium Ltd | Professional & scientific | 2024 |
| Jbdm Construction Ltd | Information & communication | 2025 |
| JEK Props Ltd | Information & communication | 2025 |
| JHJ Property Limited | Real estate | 2018 |
| Jibgn Ltd | Real estate | 2003 |
| Jimmy Bumble Ltd | Information & communication | 2026 |
| JJ Roofing Supplies Limited | Wholesale & retail | 1989 |
| JJH Rigging Services Ltd | Information & communication | 2023 |
| JJJ Productions Ltd | Information & communication | 2015 |
| Jjzed Ltd | Health & social care | 2024 |
| JK Productions Ltd | Manufacturing | 2022 |
| JON Harris Rigging Services Limited | Information & communication | 2011 |
| Joshua Myles Workshop Ltd | Administrative & support | 2022 |
| JPA Design Engineering Ltd | Professional & scientific | 2016 |
| JRG Plastering Limited | Construction | 2025 |
| JRG Plasterworks Ltd | Information & communication | 2021 |
| JSJ Plastering Ltd | Information & communication | 2025 |
| Jxdr Ltd | Information & communication | 2021 |
| JYB Property Limited | Real estate | 2022 |
| K H Scenic Services Ltd | Information & communication | 2024 |
| Kamas Property Group Ltd | Construction | 2020 |
| KAR Training Solutions Limited | Education | 2014 |
| Karriqi Property Ltd | Real estate | 2019 |
| Karriqi Property to LET Ltd | Real estate | 2024 |
| KI Venture Holdings Ltd | Real estate | 2026 |
| Kick Properties Ltd | Real estate | 2022 |
| Kildsmade Investments Limited | Construction | 1962 |
| Kingswood Drive Flat Management Company Limited | Households | 1993 |
| Kirt Technologies Ltd | Information & communication | 2023 |
| L E B Scenery Ltd | Information & communication | 2011 |
| L H Scenic Painting Ltd | Information & communication | 2022 |
| L&C Jackson Services Ltd | Construction | 2022 |
| L.E.F. Robotics Ltd | Professional & scientific | 2022 |
| Last Second.Com Limited | Real estate | 2004 |
| Laura Perkins (UK) Ltd | Other services | 2017 |
| Lawes Pascal Homes Ltd | Real estate | 2024 |
| LB Scenery Ltd | Information & communication | 2022 |
| LEE Close (New Barnet) Management Company Limited | Households | 1996 |
| Lewis Drones Limited | Administrative & support | 2023 |
| Liam Mccann SET Construction Ltd | Manufacturing | 2021 |
| Limitless Universal Ltd | Professional & scientific | 2017 |
| Little Heath Builders Ltd | Construction | 2020 |
| Lollyprop Limited | Manufacturing | 2018 |
| Long Street & Water Street Ltd | Financial services | 2025 |
| Lora Invest Ltd | Real estate | 2024 |
| LPS Electricians Ltd | Construction | 2026 |
| LRH Business Services Ltd | Health & social care | 2023 |
| Lusso Tile Studio Ltd | Construction | 2025 |
| Luxeline Chauffeurs Ltd | Transport & logistics | 2025 |
| Luxeog Ltd | Wholesale & retail | 2024 |
| M Ridout Rigging Ltd | Information & communication | 2018 |
| M&D Manor RTM Company Limited | Real estate | 2023 |
| M. Bradbrook Electrical Services Limited | Construction | 2016 |
| M. James. Associates Limited | Real estate | 1999 |
| Maaruthi Rudraa Investments Ltd | Financial services | 2025 |
| Mainline Environmental Services LLP | | 2013 |
| Mainline Environmental Systems Limited | Construction | 2000 |
| Mainline Properties Limited | Construction | 2014 |