| Dexter & Sharpe Audit Services Ltd | Professional & scientific | 2010 |
| Dexter & Sharpe Consultancy Limited | Professional & scientific | 1998 |
| Dexter & Sharpe Limited | Professional & scientific | 2024 |
| Dexter Healthcare Limited | Health & social care | 2021 |
| Dinky DOT Ltd | Wholesale & retail | 2025 |
| Dogdyke Pumping Station Preservation Trust | Arts & recreation | 2009 |
| Dressed Boxes Digital Ltd | Wholesale & retail | 2025 |
| Drova Mechanics Ltd | Professional & scientific | 2026 |
| E-Volve 20 Ltd | Wholesale & retail | 2016 |
| E.K.M. Limited | Professional & scientific | 2003 |
| East Coast Windpower Limited | Administrative & support | 2006 |
| ED Hall Services Holdings Limited | Financial services | 2024 |
| ED Hall Services Limited | Water & waste | 2004 |
| EGG Enterprises Limited | Real estate | 2005 |
| EGG Farming Company Ltd | Agriculture & fishing | 2019 |
| Electrotechnical Group Ltd | Financial services | 2024 |
| Elite Health Solutions Limited | Real estate | 2006 |
| Elliott (Hagworthingham) Limited | Hospitality | 2020 |
| Endyke Tyres Limited | Wholesale & retail | 2012 |
| Equinox Outdoor Learning CIC | Education | 2021 |
| Equip My School Limited | Wholesale & retail | 2007 |
| Everton Bros. (Poultry) Limited | Agriculture & fishing | 1977 |
| Everton Construction Services Limited | Construction | 2004 |
| Exploding INK Limited | Other services | 2013 |
| F&R Vehicle Services Ltd | Wholesale & retail | 2024 |
| F.H. Manning Financial Services Limited | Financial services | 1975 |
| F.W. Cupit (Printers) Limited | Information & communication | 1975 |
| Fast Toys Ltd | Administrative & support | 2001 |
| Fenwell & Co Lincs Ltd | Wholesale & retail | 2026 |
| Ferias Leisure Limited | Hospitality | 2020 |
| Fids Electrical Ltd | Construction | 2025 |
| Findertag Limited | Professional & scientific | 2001 |
| Flowerbite Ltd | Arts & recreation | 2014 |
| Focusglade Limited | Households | 1989 |
| Forum Packaging Limited | Manufacturing | 2011 |
| Fourseasons Landscape Gardening Maintenance Limited | Administrative & support | 2016 |
| Fuelled by Nature Limited | Agriculture & fishing | 2011 |
| Fulletby Motors (2002) Limited | Wholesale & retail | 2002 |
| Function First LLP | | 2015 |
| Gaim Consulting Ltd | Professional & scientific | 2021 |
| Garden Grafters Limited | Administrative & support | 2003 |
| Geobex Consulting Ltd | Professional & scientific | 2025 |
| GF Design Services Ltd | Professional & scientific | 2020 |
| Gladstone House Ltd | Construction | 2016 |
| Glow & Go Tanning Studios Ltd | Other services | 2026 |
| GMB Joinery Limited | Construction | 2002 |
| Go-Lion Construction Ltd | Construction | 2023 |
| Gold Star & Associates Limited | Administrative & support | 2015 |
| Goodie Shine Ltd | Administrative & support | 2026 |
| Grange Farms (West Ashby) Limited | Agriculture & fishing | 2006 |
| Grange Services Agricultural Limited | Professional & scientific | 2019 |
| Gray Infotech Limited | Administrative & support | 2016 |
| Green Investment in Greater Lincolnshire Limited | Professional & scientific | 2024 |
| Greenfield Management Limited | Professional & scientific | 2012 |
| Grimsby Property Development Ltd | Real estate | 2022 |
| Grod Lincs Limited | Construction | 2017 |
| GST Mechanical Engineering Ltd | Professional & scientific | 2007 |
| H.J. Shuttleworth and SON Limited | Agriculture & fishing | 1954 |
| Haddington Commercials Ltd | Wholesale & retail | 2025 |
| Haddington Contracting Ltd | Transport & logistics | 2021 |
| Haltham Drainage Management (1996) Limited | Households | 1996 |
| Haltham Travel Ltd | Transport & logistics | 2016 |
| Harmonious HR Ltd | Administrative & support | 2024 |
| Harpars Bar Limited | Hospitality | 2012 |
| Harvest Renewable Energy Limited | Agriculture & fishing | 2004 |
| Heating Professionally Limited | Construction | 2025 |
| Highlander Farm (Lincs) Ltd | Agriculture & fishing | 2022 |
| Hkur Ltd | Transport & logistics | 2021 |
| HOE Hill Limited | Extraterritorial | 2020 |
| Holmbridge Financial Services Limited | Financial services | 2013 |
| Home Truths Interiors Limited | Professional & scientific | 2017 |
| Homewild Limited | Households | 1982 |
| Horncastle Cricket Club Ltd. | Arts & recreation | 2026 |
| Horncastle Education Trust | Education | 2012 |
| Horncastle EYE Care Limited | Health & social care | 2010 |
| Horncastle Pizza&Kebab Ltd | Hospitality | 2024 |
| Horncastle Playing Fields (Management) Limited | Other services | 1993 |
| Horncastle Town FC Trading Ltd | Hospitality | 2015 |
| Hoytb Productions Ltd | Arts & recreation | 2022 |
| Humber Grain Limited | Agriculture & fishing | 2011 |
| Hunt Roofing and Property Services Limited | Construction | 2018 |
| Hyland Property Ltd | Real estate | 2019 |
| I.J Building Contractors Limited | Construction | 1999 |
| IF Investments (Horncastle) Limited | Manufacturing | 2019 |
| IMP Rigging Limited | Information & communication | 2018 |
| Inizio (UK) Ltd | Professional & scientific | 2014 |
| Inspired Travel UK Limited | Administrative & support | 2006 |
| Interlectrical Limited | Construction | 2018 |
| Invest East Lindsey Limited | Construction | 2019 |
| Invixon Holdings Limited | Water & waste | 2024 |
| Invixon Limited | Water & waste | 2014 |
| J & R LEE Properties Limited | Real estate | 2025 |
| J D Hitchborne Housing Ltd | Real estate | 2020 |
| J L Tyres & Vehicle Repairs Ltd | Wholesale & retail | 2023 |
| J R D Tree Services Ltd | Agriculture & fishing | 2016 |
| James Rutter Limited | Extraterritorial | 1963 |
| JAY DEE Transport Ltd | Transport & logistics | 2009 |
| Jazzy Hire Ltd | Administrative & support | 2025 |
| JB Properties 24 Ltd | Real estate | 2024 |
| Jb's Sports Coaching Ltd | Arts & recreation | 2015 |