| Falconwood Design and Project Management Ltd | Construction | 2022 |
| Famous Four Holdings Limited | Financial services | 2003 |
| Famous Four Products Limited | Wholesale & retail | 1997 |
| Famousfour.Com Limited | Extraterritorial | 2002 |
| Farmweld Services Ltd | Manufacturing | 2006 |
| FDP Security & Consultancy Services Limited | Administrative & support | 2022 |
| Feel Good Studio & Gym, Louth Limited | Arts & recreation | 2017 |
| Fenwold Properties LLP | | 2019 |
| Ferhall Ltd | Transport & logistics | 2021 |
| Fewsion Ltd | Construction | 2008 |
| Fiddle Fern Estates Ltd | Hospitality | 2022 |
| Fiddle Fern Limited | Manufacturing | 2017 |
| Fieldpound Limited | Professional & scientific | 2003 |
| FIG & Fern Floral Limited | Wholesale & retail | 2023 |
| Figura Aesthetics Ltd | Other services | 2019 |
| Finch Arboriculture Ltd | Administrative & support | 2019 |
| Fine Artlincs Limited | Manufacturing | 1978 |
| Fire Safety First Limited | Public administration | 2025 |
| First Meals Limited | Hospitality | 2017 |
| First Media (Holdings) Limited | Extraterritorial | 2014 |
| First Media Solutions Limited | Information & communication | 1999 |
| First Media Technologies Limited | Professional & scientific | 2003 |
| Fisair UK Ltd | Energy | 2019 |
| Five Oaks Limited | Real estate | 2003 |
| Fizzy Foal Ltd | Hospitality | 2022 |
| Fleur DE Force Limited | Information & communication | 2013 |
| Flexecomuk Ltd | Information & communication | 2026 |
| Flexi PIG Solutions Limited | Construction | 2021 |
| Flexi Storage Limited | Construction | 2025 |
| Flexi VET Solutions Limited | Construction | 2025 |
| Flexidig Limited | Construction | 2002 |
| Florins Pensions & Investments Ltd | Administrative & support | 2009 |
| Florins Property Limited | Real estate | 2020 |
| Florins Wills & Probate Ltd | Professional & scientific | 2014 |
| FMC Drone Services Ltd | Information & communication | 2022 |
| Food Guys Louth Ltd | Hospitality | 2025 |
| Four Woods Limited | Manufacturing | 2004 |
| Foxall and Young Construction Ltd | Construction | 2026 |
| Foxcon Building Limited | Construction | 2021 |
| Foxhall Construction Limited | Construction | 2002 |
| Foxhall Plant Hire Limited | Administrative & support | 2019 |
| Franberry Holdings Limited | Real estate | 2026 |
| Freddie’S Foods Louth Ltd | Wholesale & retail | 2017 |
| Freeday Limited | Professional & scientific | 1998 |
| Freedom Dentistry Consultancy Ltd | Extraterritorial | 2020 |
| French HDD Ltd | Construction | 2025 |
| Fresh Trim Louth Ltd | Other services | 2026 |
| Friends of Ferguson Heritage Limited | Professional & scientific | 1995 |
| Fuel Lockers Limited | Wholesale & retail | 2026 |
| Functional LNX1 Ltd | Arts & recreation | 2025 |
| Functional Project Limited | Information & communication | 2023 |
| G and T Property Lincs Limited | Real estate | 2024 |
| G Grant Rigger Ltd | Construction | 2025 |
| G Grant Rigging Services and Construction Limited | Construction | 2017 |
| G I Surplus Ltd | Wholesale & retail | 2003 |
| G L Evans Construction Ltd | Construction | 2011 |
| G Martin Electrical Limited | Construction | 2016 |
| G R S Electrical Services Limited | Construction | 1998 |
| G. Harniess (Louth) Limited | Wholesale & retail | 1984 |
| G.& B.Dobson Limited | Agriculture & fishing | 1971 |
| Gary Swann (Legal Services) Limited | Professional & scientific | 2024 |
| GAS Solve Limited | Construction | 2013 |
| Gasells Ltd | Transport & logistics | 2015 |
| Gayton Valley Limited | Other services | 2016 |
| GB Potatoes Organisation Ltd | Other services | 2022 |
| GBM Asbestos Surveys Limited | Extraterritorial | 2004 |
| GBM Demolition Limited | Extraterritorial | 2017 |
| GBM Oakham Limited | Water & waste | 2024 |
| GBM UK Holdings Limited | Financial services | 2023 |
| Gemstone Equine Ltd | Wholesale & retail | 2024 |
| Genelec Diesels Limited | Manufacturing | 2007 |
| Genpow Ltd | Construction | 2021 |
| George Chubb Golf Ltd | Wholesale & retail | 2025 |
| GHA Investments Limited | Financial services | 2021 |
| Giadia Ltd | Construction | 2025 |
| GIL (Louth) Investment Properties Limited | Real estate | 2023 |
| Giles & Giles Limited | Real estate | 2023 |
| Giles Murfin Limited | Real estate | 2016 |
| Ginko Partnership LLP | | 2024 |
| Gleeson and Daughters Ltd | Agriculture & fishing | 2026 |
| Glo-Tek Ltd | Professional & scientific | 2021 |
| GM & RE Holdings Limited | Financial services | 2022 |
| Gnarly Tree Ltd | Agriculture & fishing | 2017 |
| GNK Holdings Limited | Construction | 2019 |
| GNK Ranmoor Ltd | Real estate | 2022 |
| Gnutti Carlo UK Ltd | Professional & scientific | 1995 |
| Go Camping UK Limited | Administrative & support | 2006 |
| Gold Bond Marine Engineering (North) Ltd | Professional & scientific | 2022 |
| Golden Phoenix Chinese Ltd | Hospitality | 2024 |
| Golden Sovereign Mines Limited | Mining & quarrying | 2025 |
| Golden Wheel (Louth) Ltd | Hospitality | 2018 |
| Gorgeous Daze Limited | Extraterritorial | 2020 |
| Gospelgate Management Company Limited | Households | 1997 |
| Gottahavebooks Ltd | Information & communication | 2015 |
| Gracechurch Consultants Ltd | Professional & scientific | 2019 |
| Grantham Bros. Limited | Agriculture & fishing | 1978 |
| Grantham Campers Limited | Wholesale & retail | 2019 |
| Grantham Industries Limited | Water & waste | 2001 |
| Graphic Impressions Limited | Water & waste | 1982 |
| Graphicgene Limited | Manufacturing | 2011 |