| Liquaid Holdings Ltd | Households | 2024 |
| Little Acres Management Limited | Households | 2018 |
| Little Diamonds Holiday Club Limited | Health & social care | 2021 |
| Little Tigers Stay and Play Ltd | Hospitality | 2026 |
| Littlehampton Angling Ltd | Wholesale & retail | 2015 |
| Littlehampton Badminton & Squash Club Limited | Arts & recreation | 1937 |
| Littlehampton Beach Court Management Company Limited | Households | 1973 |
| Littlehampton Blinds Limited | Wholesale & retail | 2018 |
| Littlehampton Bonfire Society Limited | Other services | 1997 |
| Littlehampton Cutting Tools Ltd. | Other services | 2011 |
| Littlehampton Day Nursery Community Interest Company | Health & social care | 2006 |
| Littlehampton Exotics Limited | Wholesale & retail | 2013 |
| Littlehampton Food Enterprises Ltd | Hospitality | 2024 |
| Littlehampton Garage Doors Limited | Construction | 2022 |
| Littlehampton Golf Club, Limited | Arts & recreation | 1973 |
| Littlehampton Motors Limited | Wholesale & retail | 2013 |
| Littlehampton Tyre and Exhaust Centres Limited | Wholesale & retail | 1999 |
| Littlehampton Welding (Holdings) Limited | Manufacturing | 1983 |
| Littlehampton Welding Group Holdings Limited | Professional & scientific | 2008 |
| Littlehampton Welding Limited | Manufacturing | 1995 |
| Littlehampton Yacht Club Limited | Arts & recreation | 2010 |
| Lizard Lets Ltd | Real estate | 2023 |
| Llanbobl Media Group Ltd | Information & communication | 2014 |
| Llanbobl Productions Limited | Information & communication | 2009 |
| Llanbobl Vision Ltd | Information & communication | 2014 |
| LM Curry Ltd | Hospitality | 2019 |
| LOA Court Residents Limited | Households | 2018 |
| Local Plumbing Supplies Ltd | Wholesale & retail | 2022 |
| Lockfit (Worthing) Ltd | Administrative & support | 2019 |
| Lockn Ltd | Information & communication | 2026 |
| London Clad Ltd | Construction | 2021 |
| Longwood Close Management Company Limited | Households | 2022 |
| LOU B Marketing Limited | Information & communication | 2020 |
| LOV2SUCCEED Limited | Wholesale & retail | 2012 |
| Love to Home Properties Ltd | Real estate | 2020 |
| Love Your Tent Limited | Extraterritorial | 2021 |
| LOVEGREENLIFE365 Ltd | Extraterritorial | 2015 |
| LOW Cost Fencing Ltd | Administrative & support | 2017 |
| LRD Industries Ltd | Wholesale & retail | 2021 |
| LRF Services Ltd | Administrative & support | 2024 |
| LSA Capital Limited | Real estate | 2019 |
| LSH Property Developments Ltd | Construction | 2026 |
| Lubanas Ltd | Construction | 2016 |
| Lucas Carter Ltd | Construction | 2020 |
| Lucid Solutions Ltd | Administrative & support | 2020 |
| Lukey's Express Wash Ltd | Administrative & support | 2025 |
| Lumibar Limited | Manufacturing | 2025 |
| Luna UK Consultancy Limited | Professional & scientific | 2025 |
| Luxerecovery Limited | Wholesale & retail | 2025 |
| Lydon Hutton-Burgwin LLP | | 2025 |
| M & R Stoneworks Ltd | Construction | 2017 |
| M J Brows Construction Ltd | Construction | 2015 |
| M R Media & Data Limited | Information & communication | 2013 |
| M W Spraying Ltd | Wholesale & retail | 2025 |
| M&M Formwork Ltd | Construction | 2016 |
| M.E. Hot Wash Ltd | Administrative & support | 2025 |
| M.H Autotech Ltd | Wholesale & retail | 2020 |
| Mabanzila Site Services Ltd | Administrative & support | 2025 |
| Mabruk Ltd | Professional & scientific | 2016 |
| Mabuhay Properties Limited | Real estate | 2024 |
| MAC Clan Consulting Limited | Information & communication | 2012 |
| Macauley Place Residents Limited | Households | 2018 |
| Mada Music Entertainment Limited | Arts & recreation | 2010 |
| Mada Music Publishing Limited | Arts & recreation | 2016 |
| Madebysi Limited | Professional & scientific | 2014 |
| Madehurst Court Residents Association Limited | Households | 1986 |
| Magejato Ltd | Real estate | 2014 |
| Magic Carpet Films Limited | Professional & scientific | 2019 |
| Magickal Moments Ltd | Wholesale & retail | 2025 |
| Magpie & Mandarin Limited | Professional & scientific | 2022 |
| Maisha Tandoori Ltd | Hospitality | 2026 |
| Make My Life Simple Limited | Extraterritorial | 2018 |
| Mali Construction Limited | Construction | 2022 |
| Mali Homes Ltd | Construction | 2023 |
| Malo Interactive Ltd | Arts & recreation | 2026 |
| Malthouse Lettings & Property Management Limited | Real estate | 2025 |
| Mamaa Couriers Limited | Transport & logistics | 2025 |
| Mamy's Treats Ltd | Wholesale & retail | 2023 |
| Mana Studios Ltd | Hospitality | 2026 |
| Manarj Realty Ltd | Real estate | 2021 |
| Manchon UK Limited | Real estate | 2021 |
| Manhandle Press Ltd | Transport & logistics | 2013 |
| Manor Ceilings Limited | Construction | 1999 |
| Manyother Limited | Professional & scientific | 2011 |
| Maoet Ltd | Professional & scientific | 2022 |
| Maple Lodge Investments Ltd | Real estate | 2009 |
| Maplewood Developments (108 Arundel Road Littlehampton) Residents Company Limited | Real estate | 1987 |
| Maratan UK Ltd | Transport & logistics | 2019 |
| March Road Ltd | Construction | 2024 |
| Margot K Lettings Expertise Ltd | Real estate | 2020 |
| Mariegold Care Limited | Administrative & support | 2021 |
| Marine Testing Solutions Ltd | Administrative & support | 2012 |
| Mariners Quay Apartments Limited | Real estate | 2007 |
| Mariners Quay Apartments RTM Company Limited | Real estate | 2012 |
| Mariners Walk "a" (Eastbourne) Management Company Limited | Households | 1994 |
| Marlins Investments Limited | Real estate | 2022 |
| Marlowe Burger Limited | Hospitality | 2019 |
| Marlowe Franchise Holdings Limited | Financial services | 2024 |
| Marlowe Property Holdings Limited | Hospitality | 2025 |
| Marmor Holdings Ltd | Real estate | 2026 |