| LCC Vita Consilium Limited | Real estate | 2022 |
| Leamington Key Co.Limited | Wholesale & retail | 1949 |
| Leamington Spa Specsavers Limited | Wholesale & retail | 1986 |
| Leamington Spa Visionplus Limited | Wholesale & retail | 2001 |
| Lees Agricultural Ltd | Manufacturing | 2006 |
| Left Hand Press Limited | Financial services | 2016 |
| Lets Go Property Limited | Real estate | 2004 |
| Leyton Electrical Services Ltd | Energy | 2003 |
| LGC Logistics Ltd | Transport & logistics | 2024 |
| Life-Ways | Education | 1995 |
| Lift Cert Limited | Professional & scientific | 2002 |
| Linfoot Homes Limited | Professional & scientific | 1991 |
| Lissaman Design Limited | Information & communication | 2007 |
| Litron Lasers Limited | Manufacturing | 1997 |
| Litron Limited | Professional & scientific | 1997 |
| Litron Optical Limited | Professional & scientific | 1997 |
| Live & Local Ltd. | Arts & recreation | 1994 |
| Logical Computers Limited | Wholesale & retail | 1995 |
| Loveworks Ltd | Professional & scientific | 2006 |
| LT Consultancy Services Ltd | Information & communication | 2016 |
| Lucky Go Co., Limited | Information & communication | 2024 |
| Lynton Child Care Limited | Education | 2003 |
| Lyrima Limited | Professional & scientific | 2000 |
| M S Birk Pharmacy Limited | Wholesale & retail | 1998 |
| M. K. H. Limited | Construction | 2000 |
| M.D. Transport Rugby Limited | Transport & logistics | 2007 |
| M.G.M. Financial Management Limited | Professional & scientific | 2002 |
| MAC Warewashing Service Limited | Manufacturing | 2008 |
| Macham Contractors Ltd | Construction | 2004 |
| MAD Fish Swim School Limited | Education | 2003 |
| Magiprint Limited | Manufacturing | 2001 |
| Maidgreen Ltd | Administrative & support | 2014 |
| Malcolm Nicholls Limited | Manufacturing | 1978 |
| Malosa Limited | Manufacturing | 2001 |
| Manjit Haulage Limited | Transport & logistics | 2005 |
| Manor House (Kenilworth) Limited | Wholesale & retail | 2000 |
| Marble Hill Partners Limited | Administrative & support | 2007 |
| Margarets Country Kitchen Confectionery Ltd | Manufacturing | 2001 |
| Marine Engine Services (Midlands) Ltd | Manufacturing | 2000 |
| Mark Boult Ltd | Manufacturing | 1960 |
| Mark Eales Heating Services Limited | Construction | 2006 |
| Marson, Rathbone Taylor LLP | | 2007 |
| Massey Hawkins Limited | Hospitality | 2007 |
| Master GI Relax Massage and Beauty Therapist Ltd | Other services | 2021 |
| Matrix Wealth Limited | Administrative & support | 2023 |
| Mayfields Management Company Limited | Households | 1999 |
| Mayura Ambaal Ltd | Wholesale & retail | 2023 |
| Mcbeath & Co. (Warwick) Limited | Wholesale & retail | 1926 |
| MCI Electrical Installations Ltd | Energy | 2007 |
| Mclaren Design Limited | Extraterritorial | 1998 |
| Mclean Restaurants Limited | Hospitality | 2001 |
| MCP Consulting Group Limited | Professional & scientific | 2000 |
| Medical Prescription Services Ltd. | Health & social care | 1999 |
| MEER2025 LLP | | 2025 |
| Mercia Energy Limited | Professional & scientific | 2003 |
| Mercury XRM Limited | Information & communication | 2014 |
| Metrocraft Limited | | 1984 |
| Midelec Limited | Arts & recreation | 1978 |
| Midvale Garage (Rugby) Limited | Wholesale & retail | 1987 |
| Milby Nursery & Kids Club | Other services | 2012 |
| Millstrom Limited | Households | 2005 |
| Milton Park Management Limited | Real estate | 1993 |
| Minke Limited | Professional & scientific | 2003 |
| Mint Pubs and Restaurants Limited | Hospitality | 2007 |
| Mintsource Consulting Ltd | Information & communication | 2014 |
| Mira Technology Park Services Limited | Real estate | 2023 |
| Mixed Reality Limited | Information & communication | 2000 |
| MKL Tools Limited | Manufacturing | 1983 |
| Molson Compact Equipment Limited | Wholesale & retail | 2003 |
| Monera Limited | Other services | 1995 |
| MOO Design Limited | Professional & scientific | 2003 |
| Motorvate UK Limited | Education | 2003 |
| MR. Fox's Spice Shops Limited | Professional & scientific | 1989 |
| MR. Fox's Spices Limited | Professional & scientific | 1989 |
| MSC Charity Trust | Other services | 2017 |
| Multidrive Limited | Manufacturing | 2007 |
| Murley Agricultural Supplies Limited | Extraterritorial | 1959 |
| Murley Auto Limited | Wholesale & retail | 1986 |
| Murley Limited | Financial services | 1986 |
| N.F.U. Mutual Management Company Limited | Financial services | 1982 |
| Nath Limited | Information & communication | 2007 |
| National Farmers Union Mutual Insurance Society Limited(The) | Financial services | 1910 |
| Nautic Products Limited | Professional & scientific | 1999 |
| NE Properties Limited | Professional & scientific | 2000 |
| Neary's Developments Limited | Other services | 2020 |
| Network Pc's Limited | Information & communication | 1997 |
| New Town Printers (Redditch) Limited | Manufacturing | 1950 |
| Newbold Energy Ltd | Water & waste | 1956 |
| Newborough Networks Limited | Information & communication | 2004 |
| Newbridge Straw Products Ltd | Agriculture & fishing | 2005 |
| NFU Mutual (Service Company) Limited | Administrative & support | 2004 |
| NFU Mutual Investment Services Limited | Financial services | 1984 |
| NFU Mutual Risk Management Services Limited | Administrative & support | 1997 |
| NFU Mutual Select Investments Limited | Financial services | 2012 |
| Nicholls Engineering Systems Limited | Manufacturing | 1986 |
| Niobium Management Limited | Real estate | 2006 |
| Normandy House Management Limited | Households | 2005 |
| Novamark Consulting Limited | Professional & scientific | 2003 |
| NRA Estates Limited | Construction | 2007 |
| NSI Group Limited | Wholesale & retail | 1973 |