| Four One Four Ltd | Bury St Edmunds | 2003 |
| Four Park Town Limited | Consett | 2019 |
| Four Pillars Life Ltd | Glasgow | 2022 |
| Four Quarters Sports Limited | London | 2025 |
| Four Seasons Entertainment Ltd | Abertillery | 2011 |
| Four Seasons Golf Centre Limited | Derby | 2007 |
| Four Seasons Health and Leisure Club Ltd | London | 2011 |
| Four Sides London Limited | London | 2013 |
| Four Space Joinery Ltd | Watford | 2023 |
| Four Star Films Limited | London | 1958 |
| Four Storey House Ltd | Banbury | 2013 |
| Four Toed Lotus Limited | Harrow | 2024 |
| Four Walls Fitness Limited | Teddington | 2016 |
| FOUR19 Fitness Limited | Bath | 2024 |
| FOUR40 Ltd | Birmingham | 2017 |
| FOUR55 Limited | Walthamstow | 2012 |
| FOUR5’S Submission Grappling Ltd | Weston-Super-Mare | 2024 |
| Fourcast Music Limited | London | 2026 |
| Fourcorner Club Limited | London | 2022 |
| Fourfour Music School Ltd | Mapperley | 2018 |
| Fourge Ltd | London | 2025 |
| Fourm Studio Ltd | Stevenage | 2026 |
| Fourmy Studio Ltd | Ashford | 2026 |
| Fournor Ltd | London | 2022 |
| Foursaturn Films Ltd | Plymouth | 2024 |
| Fourstudios Ltd | London | 2026 |
| Fourteen Arrows Tattoo Ltd | Tunbridge Wells | 2023 |
| Fourteen Fit HQ Ltd | Milton Keynes | 2025 |
| Fourteen Forty-Six Limited | Shrewsbury | 2019 |
| Fourteen Talent Group Ltd | Haywards Heath | 2021 |
| Fourth Drawer Limited | Tunbridge Wells | 2026 |
| Fourth Idea CIC | Shipley | 2025 |
| Fourth Ordinal Ltd | Glasgow | 2024 |
| Fourth Quarter Fitness Ltd | Bradford | 2023 |
| Fourth Wall Folkestone CIC | Ramsgate | 2022 |
| Fourth Wall Live Limited | London | 2020 |
| Fourth Wall Padel Ltd | Bury St. Edmunds | 2025 |
| Fourth Wall Theatre Entertainment Ltd | London | 2020 |
| Fourth Wall Theatrical Limited | London | 2022 |
| Fourthcape Limited | Cowes | 2013 |
| Fourthwall Attraction Ltd | London | 2024 |
| Fourthwall Holdings Ltd | London | 2024 |
| Fowlc Community Interest Company | Wadebridge | 2022 |
| Fowler Fitness Ltd | London | 2018 |
| Fowles Entertainment UK Ltd | London | 2020 |
| Fowles Fitness Limited | Leighton Buzzard | 2015 |
| Fowley Marine(Emsworth)Limited | Emsworth | 1962 |
| FOX & Grace Limited | Haddington | 2021 |
| FOX & Lark Limited | Nottingham | 2005 |
| FOX & Shannon Ltd | Sutton | 2014 |
| FOX & the Magpie Ltd | Ilkley | 2012 |
| FOX Academy of Dance Ltd | Needham Market | 2022 |
| FOX and Badge Ltd | London | 2019 |
| FOX and Hound Theatre Ltd | Castle Douglas | 2025 |
| FOX Audio Ltd | Carterton | 2024 |
| FOX Base Alpha Industry Ltd | Brighton | 2025 |
| FOX Busters Limited | Gloucester | 1987 |
| FOX Collective Limited | London | 2011 |
| FOX Cycling Limited | Bristol | 2019 |
| FOX Dance Academy Limited | Lancaster | 2023 |
| FOX Entertainment Ltd | London | 2025 |
| FOX Football Limited | Blackburn | 2026 |
| FOX for Fitness Limited | Lanark | 2026 |
| FOX Golf Limited | Loughborough | 2026 |
| FOX James Productions Limited | Doncaster | 2019 |
| FOX Literary Ltd | London | 2022 |
| FOX Meadow Equestrian Limited | Lichfield | 2008 |
| FOX Physique Limited | Nottingham | 2015 |
| FOX Records Limited | Abingdon | 2009 |
| FOX Stevenson Music Limited | London | 2015 |
| FOX the G Limited | St. Albans | 2025 |
| FOX Trading and Events Ltd | Derby | 2023 |
| FOX Training (UK) Ltd | Chichester | 2005 |
| FOX Velocity Ltd | Coggeshall | 2025 |
| Foxash Equestrian Ltd | Manningtree | 2016 |
| Foxbury Allotments Limited | Bromley | 2020 |
| Foxbury Springs Limited | London | 2020 |
| Foxco Global Ltd | Basildon | 2024 |
| Foxcote House Riding School Limited | Cheltenham | 2014 |
| Foxcraft Racing Limited | Romsey | 2020 |
| Foxdenton Farm Riding School Limited | Manchester | 2022 |
| Foxdog Studios Ltd | Manchester | 2012 |
| Foxes & Bears Sports Limited | Haywards Heath | 2025 |
| Foxes DEN Entertainment Ltd | Manchester | 2025 |
| Foxes Productions Limited | London | 2019 |
| Foxes Shows Limited | Bootle | 2014 |
| Foxfit Conditioning Ltd | Crowthorne | 2025 |
| Foxfit Cumbernauld Ltd | Cumbernauld | 2018 |
| Foxflare Sports Ltd | Lichfield | 2025 |
| Foxglade Showjumping Limited | Corby | 2020 |
| Foxglove Entertainments Limited | London | 2001 |
| Foxhall Sporting Club Ltd | Cheltenham | 2026 |
| Foxhangers Limited | Devizes | 2012 |
| Foxhill Indoor Bowls Club Limited | Buckinghamshire | 1992 |
| Foxhills Racing Limited | Bristol | 2020 |
| Foxhound Riding School Limited | Essex | 1966 |
| Foxlake Adventures Community Interest Company | East Linton | 2012 |
| Foxley Club Limited | Hereford | 2015 |
| Foxley Creative Limited | Harrow | 2023 |
| Foxlowe Arts Centre Ltd | Leek | 2011 |