| Families Chiltern Limited | Information & communication | 2015 |
| Family Flow Ltd | Health & social care | 2021 |
| Family Homes Management Ltd | Real estate | 2021 |
| Farm House Pizza (Bucks) Ltd | Hospitality | 2017 |
| Farsee Ltd | Professional & scientific | 2022 |
| Farset Commercial Maintenance Ltd | Construction | 2020 |
| Fashion UK Limited | Wholesale & retail | 2002 |
| Fast Car Audio Ltd | Wholesale & retail | 2018 |
| Fast Track Services (Southern) Limited | Administrative & support | 2007 |
| Fastway Management Ltd | Professional & scientific | 2001 |
| Fattoria SAN Paolo Ltd | Wholesale & retail | 2013 |
| FB Arndale Limited | Real estate | 2018 |
| FB Baker Street Ltd | Real estate | 2024 |
| FB Brighton Limited | Real estate | 2013 |
| FB Coventry Ltd | Real estate | 2016 |
| FB Coventry Street Ltd | Real estate | 2019 |
| FB Croydon Ltd | Hospitality | 2021 |
| FB Drinks UK Ltd | Wholesale & retail | 2020 |
| FB Ealing Ltd | Real estate | 2015 |
| FB Hammersmith Ltd | Real estate | 2019 |
| FB Harrow Ltd | Real estate | 2014 |
| FB Ilford Ltd | Real estate | 2020 |
| FB Liverpool Ltd | Real estate | 2018 |
| FB Southampton Limited | Real estate | 2022 |
| FB Staines Ltd | Real estate | 2017 |
| FB Supermarkets Limited | Real estate | 2014 |
| FB Watford Ltd | Real estate | 2022 |
| FB Woking Ltd | Real estate | 2013 |
| FB Wycombe Limited | Real estate | 2021 |
| FEF Grazing Limited | Agriculture & fishing | 2024 |
| Felbury House Ltd | Health & social care | 2011 |
| FEN Bear Properties Limited | Real estate | 2014 |
| Fenton Civil Engineering Limited | Construction | 2006 |
| Fenton Landscapes Limited | Administrative & support | 2023 |
| Fenton Plant Hire Limited | Administrative & support | 2016 |
| Fernberg Limited | Administrative & support | 2016 |
| FF Land Holdings Limited | Real estate | 2021 |
| FFS Fitness Limited | Arts & recreation | 2017 |
| FHG Advisory Limited | Financial services | 2009 |
| Fido Consulting Limited | Real estate | 1998 |
| Field Associates Limited | Real estate | 2019 |
| Film Works International Ltd | Information & communication | 2022 |
| Financial Strategic Solutions Ltd | Other services | 2020 |
| Finecropt Management Co. Ltd. | Households | 1992 |
| Finesystem Ltd | Information & communication | 1993 |
| Finger Frame Productions Ltd | Information & communication | 2024 |
| Finita Cctv and Security Limited | Administrative & support | 2022 |
| Finita Limited | Administrative & support | 2015 |
| Fire Safety SPH Ltd | Financial services | 2021 |
| Firefly Construction Limited | Construction | 2015 |
| Firetec Limited | Construction | 1991 |
| First Darvell Drive RTM Company Limited | Households | 2003 |
| First in Class Limited | Professional & scientific | 2025 |
| Fitness Club Phoenix Ltd | | 2009 |
| Five Property Services Ltd | Real estate | 2025 |
| FIX My Pension Ltd | Extraterritorial | 2009 |
| Fixmypension.Com Limited | Extraterritorial | 2009 |
| FK Holdings Ltd | Real estate | 2018 |
| Flamecheck Limited | Administrative & support | 2017 |
| Flamstead Farm Management Limited | Extraterritorial | 2005 |
| Flat Frog Films Ltd | Information & communication | 2009 |
| FLO Consult UK Limited | Professional & scientific | 2013 |
| Flomark Limited | Professional & scientific | 2017 |
| Florian Fire Safety Ltd | Professional & scientific | 2025 |
| FLS Management Ltd | Real estate | 2019 |
| FLUENT2 IT Limited | Information & communication | 2009 |
| Flutesteps Limited | Other services | 2011 |
| FLY Tyres Chesham Ltd | Wholesale & retail | 2026 |
| Flying Disabled Ltd | Transport & logistics | 2020 |
| Flying Formations Limited | Professional & scientific | 2011 |
| Flynnandson Limited | Construction | 2008 |
| FMP Financial Services LLP | | 2017 |
| Focus 8 Media Ltd | Professional & scientific | 2020 |
| Fold Studio Scarves Ltd | Wholesale & retail | 2026 |
| Folio Properties (Herts) Limited | Real estate | 2019 |
| Foraged by Fern Ltd. | Agriculture & fishing | 2025 |
| Fordingbridge Developments Limited | Real estate | 2005 |
| Forebury Consulting Ltd | Professional & scientific | 2023 |
| Forensic Psychology Network Ltd | Health & social care | 2024 |
| Forensic Psychology Services Ltd | Health & social care | 2007 |
| Formact Limited | Administrative & support | 2012 |
| Formaldeal Property Management Limited | Households | 1994 |
| Formative Impact Ltd | Professional & scientific | 2024 |
| Forte Pizza Limited | Hospitality | 2026 |
| Fortitude Media Limited | Information & communication | 2026 |
| Fortuna Home & Lifestyle Limited | Financial services | 2023 |
| Foster Installations (Hemel) Limited | Manufacturing | 2020 |
| Foster Installations Limited | Manufacturing | 2013 |
| Founder Facilitation Services Limited | Extraterritorial | 2024 |
| Fountain of Peace Children's Foundation UK | Health & social care | 2006 |
| FOX Precision Machine Limited | Manufacturing | 1975 |
| Frame Communications Limited | Professional & scientific | 1993 |
| Framecoach Ltd | Professional & scientific | 2026 |
| Framework Recruitment Ltd | Administrative & support | 2024 |
| Framing Gallery Limited | Other services | 2015 |
| Franklin Close & Chartridge Lane Management Limited | Real estate | 2020 |
| Freshly Baked (Bromley) Limited | Administrative & support | 2010 |
| Freshly Baked (Norwich) Ltd | Real estate | 2012 |
| Freshly Baked Airports Ltd | Wholesale & retail | 2016 |
| Freshly Baked EOT Limited | Administrative & support | 2025 |