| FEN Lane Carp Fisheries Limited | Agriculture & fishing | 2022 |
| Fenix Active Ltd | Arts & recreation | 2013 |
| Fenwick Brothers Limited | Agriculture & fishing | 1954 |
| Fenwick Tech Services Ltd | Construction | 2025 |
| Fetch & Carry Services Ltd | Transport & logistics | 2002 |
| FEZ Barber Limited | Other services | 2022 |
| Field House (Apartments) Management Limited | Real estate | 1984 |
| Fieldfair Ltd | Manufacturing | 2023 |
| Fieldhead Road (Laceby) Management Company Limited | Households | 2024 |
| Fifty Three Angling Club Limited | Arts & recreation | 1968 |
| Fili Management Limited | Professional & scientific | 2016 |
| Fillet Fish Holdings Limited | Financial services | 2024 |
| Fims Engines Limited | Other services | 2005 |
| Finchy Marketing Limited | Wholesale & retail | 2017 |
| Find My Rescue Ltd | Information & communication | 2025 |
| Finnegans Plant Limited | Construction | 2014 |
| FIP (UK) Ltd | Wholesale & retail | 2013 |
| Fire Fruit & VEG Ltd | Wholesale & retail | 2014 |
| Firecom Limited | Public administration | 2016 |
| Firedrop Ventures Limited | Information & communication | 2015 |
| First AID Made Easy Ltd | Health & social care | 2019 |
| First Catch (Filey) Limited | Hospitality | 2012 |
| First Cohort International Limited | Professional & scientific | 2017 |
| First Protect Ltd | Information & communication | 2013 |
| First Quantum Consulting Ltd | Information & communication | 2025 |
| First Steps Grimsby Limited | Administrative & support | 2003 |
| Fish the NET Ltd | Wholesale & retail | 2005 |
| Fitter Stronger Smarter Ltd | Education | 2015 |
| Fittest Strongest Smartest Ltd | Education | 2025 |
| Five Star Fish in Waiting Limited | Extraterritorial | 2010 |
| Fivedoubleu Ltd | Real estate | 2013 |
| FJC Engineering Services Ltd | Professional & scientific | 2019 |
| FK3 Group Ltd | Financial services | 2024 |
| FKC Property Ltd | Real estate | 2025 |
| FKP Consultancy Limited | Public administration | 2014 |
| Flame Medical Limited | Health & social care | 2015 |
| Flashform Ltd | Manufacturing | 2024 |
| Flemings Woodhall Spa Ltd | Wholesale & retail | 2024 |
| Fletcher Estates Limited | Real estate | 2024 |
| Flexi Cargo Ltd | Wholesale & retail | 2020 |
| Flightline Joinery Limited | Construction | 2019 |
| Flocktons T.V.P. Ltd | Manufacturing | 2010 |
| Floorpeople Ltd. | Administrative & support | 2021 |
| Florian&Yanis Limited | Transport & logistics | 2026 |
| Florpro Plus Limited | Construction | 2010 |
| Flourish to Empower Limited | Health & social care | 2021 |
| Flowcooling Limited | Construction | 2018 |
| Flower Solutions Limited | Wholesale & retail | 2013 |
| Flywatch Global Ltd | Transport & logistics | 2010 |
| FMD Limited Ltd | Transport & logistics | 2024 |
| FMD Logistics Ltd | Transport & logistics | 2023 |
| Focus 3 Ltd | Mining & quarrying | 2021 |
| Focus Independent Adult Social Work C.I.C. | Health & social care | 2013 |
| Food Sector Construction Limited | Construction | 2012 |
| Food Sector Engineering Ltd | Construction | 2019 |
| FOR Under Fives Limited | Education | 1990 |
| Forbes Burton Limited | Professional & scientific | 2009 |
| Forbes Burton Ventures Limited | Extraterritorial | 2017 |
| Forbes Capital Ltd | Financial services | 2009 |
| Fore Property Ltd | Real estate | 2024 |
| Forefront Training Limited | Administrative & support | 2010 |
| Foresight Developers Ltd | Construction | 2019 |
| Foresight North East Lincolnshire Ltd. | Hospitality | 2001 |
| Foresight Projects Limited | Real estate | 2019 |
| Foresims Ltd | Other services | 2025 |
| Forrester Boyd Outsourced Business Solutions Limited | Extraterritorial | 2022 |
| Forrester Boyd Trustees Limited | Administrative & support | 2021 |
| Forte Louth Limited | Other services | 2019 |
| Fortfitness Limited | Other services | 2019 |
| Forti Engineering Ltd | Construction | 2021 |
| Forti Group Ltd | Construction | 2021 |
| Fortify CDM Ltd | Construction | 2024 |
| Fortify Medical Ltd | Construction | 2022 |
| Fortify Resourcing Ltd | Administrative & support | 2024 |
| Fortify Safety Ltd | Construction | 2024 |
| Fortify Safety Supplies Ltd | Wholesale & retail | 2024 |
| Fortify Training Ltd | Education | 2024 |
| Fortis Safety Group Ltd | Professional & scientific | 2023 |
| Fortis Safety Services Ltd | Professional & scientific | 2024 |
| Fortis Therapy and Training Ltd | Health & social care | 2012 |
| Forward Thinking Communications Ltd. | Professional & scientific | 2012 |
| Fosse Water Treatment Limited | Water & waste | 2004 |
| Four Counties Tiling & Property Improvements Limited | Construction | 2014 |
| Four Seasons (Lincs) Limited | Hospitality | 2003 |
| Fourshore (OFF) Limited | Construction | 2012 |
| Foursquare Group Ltd | Financial services | 2023 |
| Foursquare Solutions Ltd | Information & communication | 2007 |
| Fovi Clothing Limited | Wholesale & retail | 2024 |
| Fowler and Holden Limited | Manufacturing | 1992 |
| FOX & Clates Ltd | Information & communication | 2025 |
| FOX Auto Electrical Limited | Wholesale & retail | 2012 |
| FOX People Management Limited | Administrative & support | 2022 |
| Foxhills (Scunthorpe Management) Limited | Real estate | 1994 |
| Foxlow Ltd | Real estate | 2022 |
| Foxtail Property Holdings Ltd | Real estate | 2026 |
| Foyle Safety & Management Limited | Professional & scientific | 2009 |
| Fozzfisk Ltd | Wholesale & retail | 2025 |
| Fraction Design Limited | Professional & scientific | 2010 |
| France Leisure Holidays Limited | Hospitality | 1991 |
| Francesca Transport Ltd | Transport & logistics | 2026 |