| Liam G Builders Limited | Construction | 2014 |
| Liam Porter Engineering Ltd | Construction | 2024 |
| LIB Stubbs Next Generation Investments Ltd | Financial services | 2024 |
| Liborix Ltd | Construction | 2021 |
| Limes Play and Learn Ltd | Education | 2015 |
| Limetree Leisure Limited | Wholesale & retail | 2023 |
| Lincoln & Lindsey Blind Society | Health & social care | 2009 |
| Lincolnshire and District Medical Services Limited | Health & social care | 2007 |
| Lincolnshire Event Planners Ltd | Other services | 2023 |
| Lincolnshire Fabrication Ltd | Construction | 2021 |
| Lincolnshire Fine Foods Ltd | Financial services | 2025 |
| Lincolnshire Gateway Academies Trust | Education | 2012 |
| Lincolnshire Honeyberry Limited | Agriculture & fishing | 2025 |
| Lincolnshire IT Limited | Information & communication | 2014 |
| Lincolnshire Live Electric Limited | Construction | 2009 |
| Lincolnshire Louth Motor Club Limited | Arts & recreation | 1977 |
| Lincolnshire Luxury Hideaways Limited | Hospitality | 2023 |
| Lincolnshire Stove Specialists Ltd | Construction | 2016 |
| Lincolnshire Tyre (Market Rasen) Co. Limited | Wholesale & retail | 2003 |
| Lincolnshire Tyre Co. Limited | Wholesale & retail | 1997 |
| Lincs Accountancy Services Ltd | Professional & scientific | 2025 |
| Lincs Barista Ltd | Hospitality | 2024 |
| Lincs Design Consultancy Ltd | Professional & scientific | 2006 |
| Lincs Pressure Washing Services Ltd | Administrative & support | 2021 |
| Lincs Prime Fresh Ltd | Wholesale & retail | 2013 |
| Lincs Repair Services Ltd | Construction | 2025 |
| Lincs TMS Ltd | Manufacturing | 2012 |
| Lincsprint Ltd | Wholesale & retail | 2026 |
| Lindsey Fuel and Energy Services Ltd | Other services | 2009 |
| Linia Developments Ltd | Construction | 2017 |
| Lisa Tomlinson Food Consultancy Ltd | Professional & scientific | 2016 |
| Little Hooves Ltd | Wholesale & retail | 2026 |
| Little Minnies Ltd | Manufacturing | 2025 |
| Livali Support Ltd | Health & social care | 2015 |
| Livestock Feeds (Grimsby) Limited | Real estate | 1947 |
| Lloyds Print Services Limited | Administrative & support | 2012 |
| LMC Electrical Services Ltd | Construction | 2025 |
| LN Glazing Specialists Ltd | Construction | 2023 |
| LN11 Ltd | Hospitality | 2025 |
| Local Uplift CIC | Professional & scientific | 2026 |
| Lockington Farms Limited | Agriculture & fishing | 2011 |
| Loki Europe Limited | Administrative & support | 2010 |
| London Road Sports Partnership Limited | Arts & recreation | 2023 |
| Longbourn Management Ltd | Professional & scientific | 2021 |
| LOS (Lincs) Limited | Professional & scientific | 2025 |
| Louth & District Hospice Limited | Health & social care | 2002 |
| Louth and District Voluntary Car Service Limited | Transport & logistics | 2011 |
| Louth Car Wash Ltd | Administrative & support | 2023 |
| Louth Cycle Centre Limited | Wholesale & retail | 2013 |
| Louth Driving Range Co Ltd | Real estate | 2018 |
| Louth Education Community Interest Company | Education | 2012 |
| Louth Fabrications Ltd | Professional & scientific | 2023 |
| Louth Glass Limited | Construction | 2020 |
| Louth Golf Club (1992) Limited | Arts & recreation | 1992 |
| Louth Home Support Limited | Other services | 2024 |
| Louth Interskill Limited | Education | 2007 |
| Louth Jazz CIC | Hospitality | 2025 |
| Louth Market Limited | Wholesale & retail | 2018 |
| Louth Market Store Ltd | Wholesale & retail | 2025 |
| Louth Navigation Trust Limited | Other services | 2007 |
| Louth Phone Repairs Ltd | Other services | 2018 |
| Louth Playgoers Society Limited | Arts & recreation | 1974 |
| Louth Removals Ltd | Transport & logistics | 2023 |
| Louth Taxis & Private Hire Ltd | Transport & logistics | 2023 |
| Louth Taxis Limited | Transport & logistics | 2008 |
| Louth Tennis and Sports Centre Limited | Arts & recreation | 2010 |
| Louth Town Action Group CIC | Wholesale & retail | 2023 |
| Louth Transformer Company Limited | Manufacturing | 1987 |
| Louth Tyre Centre and Car Wash Ltd | Administrative & support | 2023 |
| Louth Tyre Services Limited | Wholesale & retail | 2014 |
| Louth Valeting Centre Ltd | Wholesale & retail | 2026 |
| Louth Van Centre Ltd | Wholesale & retail | 2025 |
| Louth Volks World Ltd | Wholesale & retail | 2005 |
| Louth Wine Seller Ltd | Wholesale & retail | 2021 |
| Louthhandymanservices Ltd | Construction | 2024 |
| Lovelock and Berry Limited | Construction | 1967 |
| LR Challenge 4X4 Limited | Wholesale & retail | 2020 |
| LRM Results Limited | Administrative & support | 2018 |
| Lucas Aero Services Limited | Professional & scientific | 2024 |
| Lucky Draw Competitions Limited | Wholesale & retail | 2023 |
| Luda Lincs Limited | Manufacturing | 2021 |
| Luden Consultants Ltd | Professional & scientific | 2017 |
| Ludensian Books Ltd | Extraterritorial | 2015 |
| Lumaco Ltd | Other services | 2008 |
| Lumineux Holdings Limited | Financial services | 2023 |
| Lumineux Ltd | Manufacturing | 2012 |
| Lust for Life Antiques Limited | Wholesale & retail | 2025 |
| Luxury Spa's Limited | Extraterritorial | 2013 |
| Luxus Adhesives Limited | Extraterritorial | 2017 |
| Luxus Group Holdings Limited | Extraterritorial | 2003 |
| Luxus Limited | Manufacturing | 1965 |
| Lynwode Solutions Limited | Information & communication | 2011 |
| M a K Developments (Louth) Ltd | Real estate | 2014 |
| M B Services (Louth) Ltd | Wholesale & retail | 2014 |
| M L Dixon Limited | Transport & logistics | 2003 |
| M White Electrical Limited | Construction | 2021 |
| M.A. Stephenson Autos Limited | Wholesale & retail | 2002 |
| Macdonald Engineering Services Limited | Manufacturing | 1996 |
| Maddisonb&Ce Limited | Construction | 2026 |
| Magna Vitae | Arts & recreation | 2014 |