| LA Pizz Lesh Lane Ltd | Hospitality | 2024 |
| LA18 Fitness Ltd | Arts & recreation | 2025 |
| Ladybirds Photography Limited | Professional & scientific | 2019 |
| Laings Fruit and VEG Ltd | Wholesale & retail | 2016 |
| Lake District Acupuncture Ltd | Health & social care | 2010 |
| Lake District Compliance Solutions Ltd | Professional & scientific | 2026 |
| Lakeland Care Trustees Limited | Professional & scientific | 2024 |
| Lakeland Estate Services Ltd | Construction | 2025 |
| Lakeland Foot Care Clinics Ltd | Health & social care | 2017 |
| Lakeland Lettings and Developments Limited | Real estate | 2018 |
| Lakes & Mountains With Matt Limited | Arts & recreation | 2023 |
| Lakes Education Ltd | Administrative & support | 2026 |
| Lakes Electrical Services Ltd | Construction | 2025 |
| Lakes Gates Limited | Manufacturing | 2024 |
| Lakes Home Services Limited | Other services | 2026 |
| Lakes Implants and Orthodontics Limited | Health & social care | 2019 |
| Lakes Sports Development Ltd | Arts & recreation | 2022 |
| Lakes Upvc and Glazing Ltd | Construction | 2026 |
| Lakewood Joinery Limited | Construction | 2011 |
| Lara Gibbons Ltd | Hospitality | 2011 |
| Larimar Property Management Ltd | Real estate | 2013 |
| Larkin ENG Services Limited | Manufacturing | 2011 |
| Launderette (Barrow) Limited | Real estate | 1955 |
| Lawson Heating Solutions Ltd | Construction | 2023 |
| LB Personal Training Ltd | Health & social care | 2016 |
| LB Shares Ltd | Administrative & support | 2021 |
| LBH Ghuman Limited | Wholesale & retail | 2007 |
| LD Plastering & Construction Ltd | Construction | 2022 |
| Lecuro Limited | Construction | 2005 |
| LEE Neatis Financial Services Limited | Financial services | 2004 |
| LEE O'Keefe Limited | Administrative & support | 2014 |
| Leksure Ltd | Construction | 2013 |
| Lerh Engineering Ltd | Professional & scientific | 2025 |
| Lester Simpson Enterprises Limited | Arts & recreation | 2011 |
| Level UP Gaming Events CIC | Administrative & support | 2023 |
| Leybourne Fisheries Birtley Ltd | Hospitality | 2015 |
| LFL Millard Limited | Construction | 2012 |
| LGM Cars Ltd | Wholesale & retail | 2024 |
| Liftify Ltd | Professional & scientific | 2025 |
| Lilly's Services Limited | Administrative & support | 2025 |
| Lily Helen Fabrications Ltd | Construction | 2025 |
| Lina Barrow Ltd | Hospitality | 2025 |
| Linton Estates Group Ltd | Real estate | 2021 |
| Lion Property Construction Ltd | Construction | 2025 |
| Lion Property Management Limited | Real estate | 2026 |
| Liontreck Limited | Wholesale & retail | 1990 |
| Lisa Baron Ltd | Other services | 2008 |
| Little Peach Beauty Ltd | Other services | 2024 |
| Little Rebels Ltd | Arts & recreation | 2021 |
| Little Subs Barrow Ltd | Arts & recreation | 2018 |
| Little Wheels Barrow Ltd | Arts & recreation | 2021 |
| Lj's Property Renovations and Handyman Services Ltd | Construction | 2024 |
| Ljcs Properties and Developments Ltd | Construction | 2026 |
| LMP Retail Ltd | Wholesale & retail | 2026 |
| LMR Creative Ltd | Manufacturing | 2016 |
| Lobo BJJ Ltd | Arts & recreation | 2018 |
| Local Shops Barrow Limited | Wholesale & retail | 2023 |
| Lodestar Intelligence Ltd | Information & communication | 2026 |
| LOG360 Limited | Transport & logistics | 2025 |
| Londinium Building Services Ltd | Construction | 2014 |
| London Care Support Services UK Ltd | Health & social care | 2019 |
| Longfield Cars Ltd | Wholesale & retail | 2018 |
| Love Barrow Community Awards CIC | Administrative & support | 2024 |
| Love Barrow Families Community Interest Company | Health & social care | 2017 |
| LQ (Cumbria) Ltd | Arts & recreation | 2019 |
| LR Marketing Limited | Information & communication | 2022 |
| LS Safety Limited | Public administration | 2022 |
| LTW Offshore Ltd | Professional & scientific | 2024 |
| Lucidity Group Limited | Hospitality | 2017 |
| Luckyhosting Ltd | Information & communication | 2026 |
| Luker Solutions Limited | Professional & scientific | 2015 |
| Lush Avenue Hair Ltd | Other services | 2025 |
| Luxor Products Ltd | Professional & scientific | 2018 |
| LVM Estates Ltd | Real estate | 2025 |
| Lyndle Global Limited | Information & communication | 2019 |
| M & P Gadsden Consulting Engineers Ltd | Construction | 2006 |
| M and S Joinery Barrow Ltd | Manufacturing | 2025 |
| M Darby Limited | Households | 2016 |
| M I Joinery (Barrow) Limited | Construction | 2015 |
| M J Associates (UK) Limited | Administrative & support | 2002 |
| M K Mobiles Limited | Information & communication | 2008 |
| M. While Enterprises Limited | Professional & scientific | 2020 |
| M77AXB Limited | Administrative & support | 2022 |
| MA Tradex Ltd | Wholesale & retail | 2020 |
| Ma's Kitchen Barrow Limited | Hospitality | 2020 |
| Maass and Co Limited | Professional & scientific | 2015 |
| MAC Properties 2015 Limited | Real estate | 2024 |
| MACDOC24 Ltd | Wholesale & retail | 2024 |
| Macy MOO Ltd | Construction | 2023 |
| Madalina Niculina Limited | Hospitality | 2025 |
| Made in Britain Design Limited | Professional & scientific | 2021 |
| Madru Engineering Services Ltd | Professional & scientific | 2024 |
| Maguire Building & Joinery Ltd | Construction | 2024 |
| Maindee Guest House Limited | Hospitality | 2009 |
| Maps Brickwork Ltd | Construction | 2020 |
| MARCELTRANSPORT2025 Ltd | Transport & logistics | 2025 |
| Marina Courts Management Limited | Real estate | 2008 |
| Marina Suites Limited | Real estate | 2018 |
| Marine Services (Barrow) Limited | Transport & logistics | 2016 |
| Marine Terrace Green Limited | Households | 1994 |