| John Attwooll and Company(Tents)Limited | Manufacturing | 1964 |
| John Stayte Services Weston-Super-Mare Limited | Wholesale & retail | 1990 |
| Jonville Investments Limited | Real estate | 2006 |
| Joy Merriam Management Services Limited | Real estate | 1993 |
| Joy(Contractors)Limited | Wholesale & retail | 1965 |
| Jube Software Limited | Information & communication | 2008 |
| Jump Travel Limited | Administrative & support | 2002 |
| Juno Publishing & Media Solutions Limited | Information & communication | 2006 |
| JW Reeves Builders Limited | Construction | 2002 |
| K.P. Gardens (Glos) Limited | Administrative & support | 2006 |
| Kaats Limited | Professional & scientific | 2007 |
| Kadwell Financial Management Limited | Financial services | 2006 |
| Kaiju Drinks Ltd | Wholesale & retail | 2017 |
| Karen Mckenna Translations Limited | Administrative & support | 2002 |
| Karparts Cheltenham Limited | Wholesale & retail | 2004 |
| Kate Bloom Limited | Other services | 2003 |
| Katie Fforde Limited | Arts & recreation | 2005 |
| Keith Holland and Associates Limited | Health & social care | 2004 |
| Kelsoon Ltd | Real estate | 2003 |
| Kendall & Davies Limited | Professional & scientific | 1994 |
| Kevin Norris Limited | Construction | 2000 |
| Key Networks Ltd | Information & communication | 2001 |
| Kineton Broadcast Services Ltd | Administrative & support | 2018 |
| Kings - Solicitors Ltd | Professional & scientific | 2017 |
| Kirtle Ltd. | Real estate | 1996 |
| L S Training and Development Limited | Administrative & support | 2000 |
| L. W. Clutterbuck Ltd. | Wholesale & retail | 2003 |
| Lady Clare Limited | Manufacturing | 1946 |
| Lancefield Efficiency Limited | Administrative & support | 2014 |
| Lancefield Interiors Limited | Administrative & support | 2018 |
| Langford Educational Limited | Education | 2003 |
| Law & Company Decorative Living Limited | Wholesale & retail | 2004 |
| Learn Well Limited | Education | 2003 |
| LED Flex Manufacturing Limited | Manufacturing | 2018 |
| Lester Woods General Builders Limited | Construction | 2007 |
| Libby Lavender Cotswolds Ltd | Wholesale & retail | 2024 |
| Lifestory Development (Chertsey) Limited | Construction | 2021 |
| Lifestory Development Land Limited | Real estate | 2021 |
| Lillifarms Limited | Agriculture & fishing | 1983 |
| Lime Tree House Residents Association Limited | Households | 1981 |
| Lionel-Morgan Limited | Real estate | 1934 |
| Lister Communications Limited | Information & communication | 2000 |
| Little Oaks Nursery (Hartpury) Limited | Education | 2020 |
| Living on the VEG (Organics) Limited | Agriculture & fishing | 2021 |
| Lizvic Limited | Construction | 2006 |
| Lloyd Engineering Services Limited | Professional & scientific | 2007 |
| London Real Estate Development Limited | Real estate | 2013 |
| Lontec Limited | Education | 2005 |
| Lords of the Manor Hotel Limited | Real estate | 2025 |
| LPC (Trull) Limited | Professional & scientific | 1996 |
| Ludian Financial Planning Limited | Financial services | 2025 |
| Lulworth Guest House Limited | Hospitality | 2000 |
| Lydney Masonic Hall Limited | Other services | 1995 |
| Lynall Properties Limited | Real estate | 2004 |
| Lyndon Design Limited | Manufacturing | 1982 |
| Lypiatt Studio Limited | Arts & recreation | 1972 |
| M C Carpentry & Roofing Limited | Construction | 2015 |
| M D Collins Steel Buildings Limited | Manufacturing | 2003 |
| M J Brock Limited | Transport & logistics | 2007 |
| M J Warner Limited | Extraterritorial | 1984 |
| M.P.D. Exhibitions Limited | Administrative & support | 2004 |
| Macaroni Marble Limited | Wholesale & retail | 2003 |
| Made in Stroud Shop C.I.C. | Wholesale & retail | 2001 |
| Madpanic Limited | Information & communication | 2001 |
| Magna Strata Limited | Administrative & support | 2004 |
| MAH Plant Limited | Administrative & support | 2007 |
| Mail Boxes ETC (Cheltenham) Limited | Transport & logistics | 2004 |
| Mainstream Group Holdings Limited | Financial services | 2023 |
| Making Waves Technologies Limited | Information & communication | 2005 |
| Malcolm Hunt Design Limited | Professional & scientific | 2002 |
| Malvern Priors Management Company Limited | Households | 1992 |
| Mania Limited | Professional & scientific | 1994 |
| Mann Holdings Ltd. | Professional & scientific | 1982 |
| Mansfield Enterprises Ltd | Construction | 2020 |
| Manu Forti Management Limited | Professional & scientific | 1995 |
| Maple (280) Limited | Households | 2006 |
| March Creative Agencies LLP | | 2025 |
| Marchants Coaches Limited | Transport & logistics | 1993 |
| Marlborough Skips Limited | Extraterritorial | 2003 |
| Marling Floorbrand Limited | Professional & scientific | 2007 |
| Marlings Design Limited | Administrative & support | 2016 |
| Marlings Surface Design Limited | Administrative & support | 2016 |
| Marnel Building Limited | Construction | 1976 |
| Marshfield Stone Roofing Tiles Limited | Administrative & support | 2006 |
| Masstock Arable (UK) Limited | Agriculture & fishing | 1989 |
| Matthews Independent Funeral Directors Limited | Other services | 2004 |
| Matthews Leisure (UK) Limited | Other services | 2001 |
| MAY Lane Motors Limited | Wholesale & retail | 2003 |
| MCK Projects Ltd | Other services | 2006 |
| Mediawide UK Limited | Information & communication | 1999 |
| Meltcharm Products Ltd | Manufacturing | 2006 |
| Melville-Brown Limited | Administrative & support | 2001 |
| Menthe Nomineeco (Clinician) Limited | Financial services | 2023 |
| Menthe Nomineeco (Co-Invest) Limited | Financial services | 2023 |
| Menthe Nomineeco (Manager) Limited | Financial services | 2023 |
| Mercedes ALL Day Ltd | Wholesale & retail | 2026 |
| Meridian Retail Limited | Wholesale & retail | 2005 |
| Metrology Software Products Limited | Professional & scientific | 2002 |
| MF Bennion Limited | Agriculture & fishing | 2001 |
| Michael Pert Consultancy Limited | Information & communication | 2007 |