| Lionvoltelectrical Ltd | Construction | 2026 |
| Liquid Logistics Group Ltd | Transport & logistics | 2018 |
| Liquid Property Group Ltd | Real estate | 2025 |
| Little Love Photography Ltd | Professional & scientific | 2020 |
| Little Munchkins Stay and Play Limited | Health & social care | 2024 |
| Little Wonder Limited | Administrative & support | 2010 |
| Live Laugh Love Limited | Wholesale & retail | 2012 |
| Livesey Carpentry Ltd | Construction | 2022 |
| Livesey Construction Limited | Construction | 2011 |
| LJ Daniels Developments Ltd | Construction | 2022 |
| LJH Groundworks & Building Limited | Construction | 2008 |
| LK Plastering Limited | Construction | 2019 |
| LK Property Associates Ltd | Real estate | 2026 |
| Llem Ltd | Transport & logistics | 2018 |
| LLY Cyber Ltd | Information & communication | 2025 |
| LM Waste Management Ltd | Water & waste | 2016 |
| LMB Ltd | Administrative & support | 2023 |
| LNR Contractors Limited | Construction | 2020 |
| Lnrs Property Limited | Real estate | 2026 |
| LNX Group Limited | Administrative & support | 2026 |
| Local Care Work Limited | Administrative & support | 2025 |
| Local Education Ltd | Administrative & support | 2024 |
| Local Group Holdings Limited | Financial services | 2025 |
| Local Vehicle Repairs Ltd | Wholesale & retail | 2026 |
| Localplumber-Uk Ltd | Construction | 2012 |
| Localplumbingheating Limited | Construction | 2015 |
| Locked on Leisure Ltd | Wholesale & retail | 2022 |
| Lockside House Residents Management Company Limited | Households | 2025 |
| Loft Lads Ltd | Construction | 2024 |
| Lokins Car Company Limited | Wholesale & retail | 2022 |
| Lokins Holdings Limited | Financial services | 2026 |
| London Access Ltd | Administrative & support | 2012 |
| London Building Group Limited | Construction | 2015 |
| London Firewall Company Ltd | Professional & scientific | 2004 |
| London Flooring Fitters Limited | Construction | 2023 |
| London Home Solutions Ltd | Construction | 2023 |
| London Roof Cleaning UK Limited | Administrative & support | 2026 |
| Longview Secretaries Ltd | Other services | 2024 |
| Longwalk Consulting Ltd | Professional & scientific | 2024 |
| Look SEE Films Limited | Information & communication | 2010 |
| Lordem Investments Ltd | Construction | 2021 |
| Losman Limited | Administrative & support | 2010 |
| Louise Claire Millinery Ltd | Wholesale & retail | 2008 |
| Louise Condon Fitness Limited | Arts & recreation | 2016 |
| Louvaine Property Letting Ltd | Real estate | 2020 |
| Love LEO CIC | Administrative & support | 2025 |
| Love My Cleaner Wickford and Billericay Ltd | Administrative & support | 2025 |
| Lovet Limited | Administrative & support | 2014 |
| Lowery Estates Limited | Information & communication | 2024 |
| LP Contracts Limited | Administrative & support | 2020 |
| LPA Carpentry Ltd | Manufacturing | 2026 |
| LPD Property Maintenance Ltd | Construction | 2024 |
| LPT Sports Limited | Wholesale & retail | 2006 |
| LS Moore Ltd | Information & communication | 2017 |
| LS Motor Group Ltd | Wholesale & retail | 2022 |
| LSL Security and Protection Services Ltd | Administrative & support | 2024 |
| LSW 2025 Limited | Construction | 2024 |
| Lucia Rose Home Limited | Wholesale & retail | 2024 |
| Lucy Wernick Holdings Limited | Professional & scientific | 2007 |
| Luke Mardle EXP Limited | Real estate | 2026 |
| Luna Creative Communications Ltd | Professional & scientific | 2018 |
| Lupto Limited | Professional & scientific | 2020 |
| Lusant Limited | Professional & scientific | 2025 |
| Luxity Ltd | Wholesale & retail | 2025 |
| Luxury Collaborative Ltd | Administrative & support | 2025 |
| LUZ Essex Ltd | Administrative & support | 2024 |
| Lynch PM Ltd | Real estate | 2016 |
| M & C Insulation Ltd | Construction | 2021 |
| M & M Grab Hire Ltd. | Water & waste | 2003 |
| M & T Carter LLP | | 2018 |
| M a Gear Associates Ltd | Professional & scientific | 2003 |
| M and C Bespoke Joinery Limited | Construction | 2013 |
| M Bate Recruitment Ltd | Administrative & support | 2025 |
| M Butterworth Upholstery Limited | Other services | 2013 |
| M Courts Limited | Wholesale & retail | 2001 |
| M J Innovation Limited | Professional & scientific | 2012 |
| M Morris Developments Limited | Construction | 2020 |
| M Naylor Enterprises Ltd | Agriculture & fishing | 2018 |
| M Penfold Electrical Contractors Ltd | Other services | 2014 |
| M R Payne & Sons Ltd | Construction | 2020 |
| M S Alarms Limited | Other services | 2001 |
| M S L (Essex) Limited | Manufacturing | 2017 |
| M&A Motors Specialist Ltd | Wholesale & retail | 2023 |
| M&G Electrical Services Limited | Construction | 2024 |
| M&S Precision Engineers Limited | Manufacturing | 2005 |
| M&W Carpentry Contractors Ltd | Manufacturing | 2020 |
| M. R. Animal Services Limited | Professional & scientific | 2011 |
| M.A Bookkeeping & Accounting Services Ltd | Professional & scientific | 2026 |
| M.C.F. Contracts Ltd | Construction | 2003 |
| M.C.F. Modern and Classic Furniture Limited | Wholesale & retail | 1998 |
| M.D. Smith and Family | Transport & logistics | 1961 |
| M.E.C. Pipe Services Limited | Construction | 2002 |
| M.E.C. Property Services Ltd | Construction | 2019 |
| M.E.R.C.S. Ltd | Professional & scientific | 2009 |
| M.G. Systems Limited | Construction | 2001 |
| M25 Asphalt Ltd | Construction | 2020 |
| M25 Fire & Security Services Limited | Construction | 2007 |
| MAC Environmental Ltd | Construction | 2016 |
| MAC Production Services Ltd | Arts & recreation | 2026 |
| Maccabe's Ltd | Construction | 2021 |