| Longpoint Solutions Limited | Construction | 2014 |
| Longview Consulting Limited | Professional & scientific | 2003 |
| Lonsdale Gardens Management Company Limited | Households | 2009 |
| Look Ahead Hairdressing Limited | Other services | 2019 |
| Look at the Moon Ltd | Wholesale & retail | 2014 |
| Loom Electrical Ltd | Construction | 2020 |
| Loop Learning Limited | Administrative & support | 2022 |
| Loopx Ltd | Transport & logistics | 2024 |
| Loose Screws Ltd | Construction | 2017 |
| Loperwood Ltd | Professional & scientific | 2019 |
| Lorato Mogotsi Ltd | Health & social care | 2015 |
| Lordswood Developments Limited | Construction | 2023 |
| Lordswood Management Company Limited | Real estate | 2009 |
| Lordswood Property Group Ltd | Real estate | 2026 |
| Lore Hairdressing Limited | Other services | 2004 |
| Lorex Technology UK Limited | Administrative & support | 2020 |
| Lorich Developments Limited | Construction | 2018 |
| Lorima Limited | Wholesale & retail | 2017 |
| Lorini Ltd | Wholesale & retail | 2021 |
| Lorna Investments Limited | Real estate | 2019 |
| Lorraine Davis Ltd | Health & social care | 2025 |
| Lorton Distribution Limited | Extraterritorial | 2015 |
| Lorton Entertainment (Surrey) Limited | Information & communication | 2026 |
| Lorton Entertainment Limited | Information & communication | 2011 |
| Lorton Films Limited | Extraterritorial | 2009 |
| Lorton International Sales Limited | Extraterritorial | 2016 |
| Lorton Pictures Limited | Information & communication | 2026 |
| Lorton Plus Limited | Information & communication | 2024 |
| Lorton Sports Productions Limited | Information & communication | 2017 |
| Losh Tech Ltd. | Other services | 2015 |
| Lothlorian Limited | Professional & scientific | 2024 |
| Lotos Land Ltd | Real estate | 2026 |
| Lotteriaimobiliara Ltd | Wholesale & retail | 2025 |
| Lotus Partnership Ltd | Professional & scientific | 2021 |
| Lotusbkj Healthcare Ltd | Administrative & support | 2024 |
| Lotwin Limited | Professional & scientific | 2013 |
| Loubella Properties Limited | Financial services | 2014 |
| Loudon Investments Limited | Real estate | 2023 |
| Loudup Ltd | Information & communication | 2012 |
| Loudview Creativity Limited | Arts & recreation | 1996 |
| Loughlin Electrical Services Ltd | Construction | 2023 |
| Loui Car Wash Ltd | Wholesale & retail | 2017 |
| Louise Makin Ltd | Professional & scientific | 2019 |
| Love and Rage Ltd | Professional & scientific | 2024 |
| Love and Sunshine Ltd | Wholesale & retail | 2025 |
| Love Dartmouth Limited | Professional & scientific | 2021 |
| Love Office Furniture Ltd | Extraterritorial | 2011 |
| Love Office Supplies Ltd | Extraterritorial | 2011 |
| Love Silver London Limited | Wholesale & retail | 2016 |
| Love Sunshine Ltd | Manufacturing | 2025 |
| Loveable Creative Ltd | Professional & scientific | 2017 |
| Loveluxe Limited | Administrative & support | 2013 |
| Lovely Little Pubs Limited | Hospitality | 2018 |
| Loves to Save | Wholesale & retail | 2019 |
| Lovett International Limited | Real estate | 2002 |
| Loveuk Limited | Other services | 2024 |
| Loving Homes Group Ltd | Construction | 2018 |
| LOW Altitude Ltd | Professional & scientific | 2021 |
| LOW Creative Ltd | Professional & scientific | 2026 |
| Lower Banister Ltd | Hospitality | 2024 |
| Lower Itchen Fishery Limited | Agriculture & fishing | 1953 |
| Lower Wangfield Farm Limited | Wholesale & retail | 2023 |
| Lowford (UK) Limited | Hospitality | 2013 |
| Lowford Cars Limited | Wholesale & retail | 2025 |
| Lowmass Limited | Wholesale & retail | 2019 |
| Loxlow Associates Limited | Administrative & support | 1982 |
| Loyal Animal Services Ltd | Other services | 2024 |
| Loyal Studio Limited | Manufacturing | 2025 |
| Loyaldeal Services UK Ltd | Wholesale & retail | 2024 |
| Loyalty Clean Limited | Administrative & support | 2017 |
| Lozmoto Ltd | Wholesale & retail | 2019 |
| Lozno Limited | Transport & logistics | 2015 |
| LP Joinery & Interiors Ltd | Construction | 2026 |
| LP Scaffold Co Ltd | Construction | 2026 |
| LP SD One Hundred Twenty Four Limited | Wholesale & retail | 2023 |
| LP Testing Ltd | Administrative & support | 2018 |
| LPD Contracts Ltd | Construction | 2013 |
| LPI Containers Ltd | Transport & logistics | 2024 |
| Lplf Ltd | Professional & scientific | 2025 |
| LPS (Southampton) Limited | Real estate | 2014 |
| LPW Carpentry & Building Ltd | Construction | 2016 |
| LR Handy MAN Ltd | Professional & scientific | 2026 |
| LR Home Improvements Ltd | Construction | 2024 |
| Lrarchitecture Ltd | Professional & scientific | 2023 |
| LRB Decks Limited | Manufacturing | 2023 |
| Lrbh Trading Ltd | Hospitality | 2019 |
| LRP Electrical Ltd | Construction | 2014 |
| Lrsp Ltd | Households | 2018 |
| Lrsp Topco Ltd | Financial services | 2025 |
| LS Consulting & Finance Limited | Professional & scientific | 2023 |
| LS Creative Limited | Professional & scientific | 2025 |
| LS Global Partners Limited | Professional & scientific | 2025 |
| LS Mechanical Building Services Ltd | Construction | 2024 |
| LS Property Investments Ltd | Real estate | 2014 |
| LSA Southampton Limited | Hospitality | 2024 |
| LSC Inspection Services Ltd | Professional & scientific | 2019 |
| LSH Commercials Limited | Wholesale & retail | 2024 |
| Lsimion Construction Ltd | Extraterritorial | 2025 |
| LSK Estates Ltd | Real estate | 2019 |
| LSP 3 Limited | Information & communication | 2020 |