| Fortitude International Consultants Ltd | Financial services | 2026 |
| Fortitudo (101) Limited | Construction | 2020 |
| Fortitudo (104) Limited | Construction | 2020 |
| Fortitudo (108) Limited | Construction | 2020 |
| Fortitudo (112) Limited | Construction | 2021 |
| Fortitudo (113) Limited | Construction | 2021 |
| Fortitudo (115) Limited | Construction | 2022 |
| Fortitudo (116) Limited | Construction | 2021 |
| Fortitudo (118) Limited | Construction | 2021 |
| Fortitudo (121) Limited | Construction | 2021 |
| Fortitudo (124) Limited | Construction | 2022 |
| Fortitudo (126) Limited | Construction | 2023 |
| Fortitudo (134) Limited | Construction | 2021 |
| Fortitudo (137) Limited | Construction | 2022 |
| Fortitudo (140) Limited | Construction | 2022 |
| Fortitudo (154) Limited | Construction | 2021 |
| Fortitudo (155) Limited | Construction | 2022 |
| Fortitudo (Advertising) Limited | Construction | 2024 |
| Fortitudo (Bournemouth Arcade) Limited | Construction | 2024 |
| Fortitudo (Bristol Road) Ltd | Construction | 2024 |
| Fortitudo (Brunel House) Limited | Construction | 2022 |
| Fortitudo (Chewton Farm Road) Limited | Construction | 2019 |
| Fortitudo (College Road) Limited | Construction | 2024 |
| Fortitudo (Dogdean) Limited | Construction | 2023 |
| Fortitudo (Dolphin) Limited | Construction | 2018 |
| Fortitudo (Fratton) Limited | Construction | 2020 |
| Fortitudo (Havant) Limited | Construction | 2019 |
| Fortitudo (Haven Road 2) Limited | Construction | 2022 |
| Fortitudo (Hillbourne Road) Limited | Construction | 2023 |
| Fortitudo (Kingsway 2) Limited | Construction | 2023 |
| Fortitudo (Little Drove Road) Limited | Construction | 2024 |
| Fortitudo (Marine Drive) Limited | Construction | 2023 |
| Fortitudo (Marine) Limited | Construction | 2023 |
| Fortitudo (Mariner) Limited | Construction | 2019 |
| Fortitudo (Martello Park) Limited | Construction | 2020 |
| Fortitudo (Newton Aycliffe) Ltd | Construction | 2024 |
| Fortitudo (Perrybrook) Limited | Construction | 2023 |
| Fortitudo (Richmond Gardens) Limited | Construction | 2024 |
| Fortitudo (Shopwyke Lakes) Limited | Construction | 2020 |
| Fortitudo (Stocks Farm) Limited | Construction | 2024 |
| Fortitudo (Waverley House) Limited | Construction | 2023 |
| Fortitudo (Westbourne Arcade) Limited | Construction | 2024 |
| Fortitudo (Wimborne) Limited | Construction | 2025 |
| Fortitudo (Workington) Limited | Construction | 2023 |
| Fortitudo (Yarmouth Road) Limited | Construction | 2024 |
| Fortitudo Construction Limited | Construction | 2015 |
| Fortitudo Homes (Commercial Road) Limited | Construction | 2018 |
| Fortitudo Homes Limited | Real estate | 2018 |
| Fortitudo Property (Winchester KW) Limited | Construction | 2018 |
| Fortitudo Real Estate Limited | Real estate | 2024 |
| Fortris Ltd | Arts & recreation | 2025 |
| Fortuna Group Holdings Ltd | Real estate | 2022 |
| Fortuna Home Solutions Limited | Construction | 2016 |
| Fortunes Payroll Ltd | Administrative & support | 2022 |
| Forty TEN Accounting Outsourcing Limited | Professional & scientific | 2026 |
| Fortyluv Ltd | Wholesale & retail | 2025 |
| Forum Fire Safety Consultants Limited | Public administration | 2023 |
| Forza Natura Limited | Wholesale & retail | 2020 |
| Fossadev Ltd | Information & communication | 2019 |
| Fossil Developments Ltd | Construction | 2023 |
| Foster Recruitment Limited | Administrative & support | 2006 |
| Fosters Pottery Limited | Administrative & support | 1995 |
| Found Change CIC | Administrative & support | 2025 |
| Foundry 52 Limited | Information & communication | 2025 |
| Fount Property Ltd | Real estate | 2021 |
| Fountain Property Company Ltd | Real estate | 2014 |
| Fountains Labels & Packaging Ltd | Manufacturing | 2023 |
| Four Anchors Ltd | Information & communication | 2025 |
| Four Miles Consultancy Limited | Wholesale & retail | 2026 |
| Four Miles Manor Limited | Real estate | 2025 |
| Four Seasons Contract Garden Services Ltd | Administrative & support | 2009 |
| Fourie Holdings Limited | Real estate | 2022 |
| Fourneaux DE France Limited | Wholesale & retail | 1979 |
| Fourth Day Limited | Professional & scientific | 2002 |
| Fourth Street Technology Ltd | Information & communication | 2022 |
| Fourway Freehold Limited | Households | 2016 |
| FOX Homes Limited | Construction | 2000 |
| FOX Performance Limited | Wholesale & retail | 2022 |
| Foxby Hill Care Home Limited | Health & social care | 2013 |
| Foxley Photography Ltd | Information & communication | 2012 |
| Foxwood Estates Limited | Real estate | 2015 |
| Foxy Vintner Ltd | Wholesale & retail | 2014 |
| Foysals Ltd | Hospitality | 2025 |
| Fozzy Finds UK Ltd | Wholesale & retail | 2020 |
| FPM Publishing Limited | Information & communication | 2005 |
| FR Troubleshoot Ltd | Wholesale & retail | 2026 |
| Fraclinx Holdings Limited | Financial services | 2022 |
| Fraclinx Limited | Wholesale & retail | 2020 |
| Framed Eyes Ltd | Manufacturing | 2019 |
| Frames Focus Ltd | Professional & scientific | 2020 |
| Frames UP Ltd | Professional & scientific | 2013 |
| Frampton Investments Limited | Construction | 1998 |
| FRAMPTON-GEAR4PETS Ltd | Manufacturing | 2025 |
| Frances Macaulay Pashmina Limited | Wholesale & retail | 1998 |
| Franceys Consulting Ltd | Information & communication | 2019 |
| Francis Y. Limited | Administrative & support | 2020 |
| Frank Consultancy Ltd | Professional & scientific | 2023 |
| Frank Edge Auctions Limited | Wholesale & retail | 2012 |
| Franklin Media Ltd | Information & communication | 2006 |
| Frankton Trading Limited | Wholesale & retail | 2018 |