| Liberty Work & Leisure Wear Limited | Wholesale & retail | 2000 |
| Libra Nine Limited | Professional & scientific | 2022 |
| Lick IT Carlisle Limited | Hospitality | 2023 |
| Light Bulb Web Design Ltd | Information & communication | 2018 |
| Lightfoot Logistics Ltd | Transport & logistics | 2025 |
| Lightfoot Stonework Limited | Manufacturing | 2019 |
| Ligna Packaging Ltd | Administrative & support | 2024 |
| Lignothera Ltd | Wholesale & retail | 2025 |
| Lilac Publishing Limited | Information & communication | 2004 |
| Lilburn Limited | Agriculture & fishing | 2013 |
| Lilliput Lane Limited | Extraterritorial | 1982 |
| Lily Greenwood Ltd | Wholesale & retail | 2023 |
| Lilywhite Property Services Ltd | Households | 2026 |
| Limehouse (Wetheral) Management Limited | Households | 2023 |
| Limitless Properties Limited | Administrative & support | 2016 |
| Lincoln Heat Network Limited | Construction | 2024 |
| Linda Scott Associates Limited | Financial services | 2003 |
| Link Recruitment Limited | Professional & scientific | 2001 |
| Linnard Engineering Limited | Professional & scientific | 2012 |
| Linstock Castle AD Limited | Administrative & support | 2010 |
| Linstock Castle Estates Limited | Financial services | 2024 |
| Linton Tweeds Holding Company Limited | Financial services | 2013 |
| Linton Tweeds Limited | Manufacturing | 1912 |
| Lisa Anderson Interior Design Limited | Wholesale & retail | 2005 |
| Lismore Place (Carlisle) Limited | Households | 2005 |
| Litody Leisure Ltd | Hospitality | 2008 |
| Little & Coates Limited | Construction | 2002 |
| Little & Mitchell Limited | Professional & scientific | 2022 |
| Little Accounting Solutions Limited | Professional & scientific | 2012 |
| Little Chippy Carlisle Ltd | Hospitality | 2025 |
| Little Coffee CUP Limited | Wholesale & retail | 2025 |
| Little Duck Cleaning Services Limited | Administrative & support | 2015 |
| Little Hero Sports Ltd | Arts & recreation | 2017 |
| Little Italy (Kendal) Ltd | Real estate | 2018 |
| Little Lifers First AID Ltd. | Health & social care | 2017 |
| Little Owls Nursery (Carlisle) Limited | Education | 2005 |
| Little Rockets Baby Sensory Ltd | Education | 2023 |
| Littleton Farming Limited | Extraterritorial | 2017 |
| LIV Homes Ltd | Hospitality | 2018 |
| Livs Logistics Ltd | Transport & logistics | 2026 |
| LJ Plumb Solutions Ltd | Construction | 2023 |
| LJ Wilson Ltd | Agriculture & fishing | 2021 |
| LKN Holdings Ltd | Financial services | 2025 |
| LLA Consultants Ltd | Health & social care | 2014 |
| Lled Construction Ltd | Construction | 2000 |
| Lloyd Finance Limited | Extraterritorial | 1971 |
| Lloyd Lawn and Leisure Limited | Extraterritorial | 2003 |
| Lloyd Limited | Wholesale & retail | 1964 |
| Lloyd Motor Group Limited | Professional & scientific | 2018 |
| Lloyd Motors Colne Holdings Limited | Extraterritorial | 2001 |
| Lloyd Motors Colne Limited | Extraterritorial | 1958 |
| Lloyd Motors Limited | Wholesale & retail | 1976 |
| Lloyd Specialist Cars Limited | Extraterritorial | 1987 |
| Lloyd Tractor Group Limited | Financial services | 2018 |
| Lloyd Tyres Limited | Wholesale & retail | 2023 |
| LLT Cleaning & Maintenance Ltd | Hospitality | 2022 |
| LMT Property Services Limited | Real estate | 2025 |
| Local Trade Cars Limited | Wholesale & retail | 2012 |
| Loch Shaped Hole Ltd | Agriculture & fishing | 2023 |
| Lochanhead Developments Ltd | Real estate | 2018 |
| Lofty Escape Ltd | Real estate | 2026 |
| LOG Homes Finland Limited | Hospitality | 2010 |
| Logarithmic Ltd | Professional & scientific | 2024 |
| Logic Business Systems Limited | Wholesale & retail | 1986 |
| Logic Computer Maintenance Limited | Professional & scientific | 1987 |
| Logic Developments Limited | Real estate | 1989 |
| Logic Document Solutions Ltd | Information & communication | 2015 |
| Logical Lifting Solutions Limited | Administrative & support | 2024 |
| Logicware Limited | Manufacturing | 2002 |
| Logik Consulting Ltd | Information & communication | 2014 |
| Logistics Skills Partnership Limited | Education | 2025 |
| Lomas Leisure Limited | Hospitality | 2017 |
| Lomond Consumer Finance Ltd | Financial services | 2019 |
| London Cafe & Sweet Bar Limited | Hospitality | 2024 |
| London Road Shawarma Limited | Hospitality | 2024 |
| London's Road Mini Market Ltd | Other services | 2024 |
| Long MAY YOU Ride Cycles Ltd | Wholesale & retail | 2023 |
| Long MAY YOU Ride Limited | Wholesale & retail | 2018 |
| Longcake Couriers Limited | Transport & logistics | 2021 |
| Longdales Construction Limited | Construction | 2022 |
| Longhorn (Cumbria) Limited | Extraterritorial | 1985 |
| Longhorn Group Limited | Extraterritorial | 2008 |
| Longlands Developments Limited | Hospitality | 2024 |
| Longmynd Developments Limited | Construction | 2014 |
| Longstokes Consultancy Ltd | Professional & scientific | 2014 |
| Longthwaite Gardens Limited | Administrative & support | 2012 |
| Longthwaite Motor Company Limited | Wholesale & retail | 2019 |
| Longton Grange (Longton) Management Company Limited | Real estate | 2024 |
| Longtown Childcare Trust Limited | Education | 2006 |
| Longtown Cricket Club Ltd | Arts & recreation | 2006 |
| Longtown Skip Hire Limited | Water & waste | 2015 |
| Lonning Garth Properties Limited | Construction | 2010 |
| Lonsdale Park (Hackthorpe) Management Company Limited | Households | 2021 |
| Lonsdale Street Development Limited | Construction | 2023 |
| Lora’S Nigerian Kitchen & Store Ltd | Wholesale & retail | 2025 |
| Loud in Libraries CIC | Arts & recreation | 2013 |
| Loudfence UK CIC | Other services | 2023 |
| Love Your Assets With IOT Limited | Information & communication | 2021 |
| Lovio Ltd | Wholesale & retail | 2025 |
| LOW House (Armathwaite) Limited | Households | 1953 |