| Financial AID Limited | Professional & scientific | 2002 |
| Findcost Limited | Real estate | 2000 |
| Findir Limited | Information & communication | 2024 |
| Findley Steele Projects Ltd | Administrative & support | 2025 |
| Fine Castings Limited | Extraterritorial | 2002 |
| Fine English Candle Co Limited | Manufacturing | 2023 |
| Fine Print Packaging Ltd | Manufacturing | 2025 |
| Finegood Ltd | Administrative & support | 2005 |
| Finell Property Limited | Real estate | 2025 |
| Finemax Limited | Extraterritorial | 2016 |
| Finer Thread Ltd | Wholesale & retail | 2019 |
| Finesse Consulting Services Ltd | Information & communication | 2024 |
| Finest Solutions Ltd | Information & communication | 2011 |
| Finper Investments Ltd | Real estate | 2025 |
| Finx Services Limited | Administrative & support | 2026 |
| Fire Mountain Investments a Limited | Financial services | 2024 |
| Fire Risk Manchester Ltd | Construction | 2020 |
| Fire Risk One Risk Assessments Ltd | Administrative & support | 2022 |
| Fire Station Square Pottery Ltd | Manufacturing | 2017 |
| Firebrand Systems Limited | Information & communication | 2026 |
| Firegy Ltd | Public administration | 2023 |
| Fireplace and Flue Solutions Ltd | Construction | 2012 |
| Fireshield NW Ltd | Administrative & support | 2026 |
| Firetech (UK) Limited | Construction | 1994 |
| Firetech Distribution Holdings Limited | Financial services | 2024 |
| Firetech Distribution Limited | Wholesale & retail | 2024 |
| Firetech Group Limited | Financial services | 2024 |
| Firium Group Limited | Wholesale & retail | 2022 |
| First AVE Ltd | Real estate | 2025 |
| First British Services Group Ltd | Information & communication | 2015 |
| First Class Kainth’S Ltd | Real estate | 2025 |
| First Dawn Holding Limited | Households | 2021 |
| First FIX Plumbing & Heating Ltd | Construction | 2019 |
| First Floor Entertainment Limited | Arts & recreation | 2026 |
| First Haven Providers Ltd | Health & social care | 2023 |
| First Maintenance and Building Ltd | Construction | 2019 |
| First Nominees Limited | Extraterritorial | 2005 |
| First Party Studio Limited | Professional & scientific | 2025 |
| First Vision Health Care Limited | Administrative & support | 2022 |
| Fish on the Moon Limited | Education | 2021 |
| Fishing Fiend Ltd | Information & communication | 2020 |
| Fisk & Co Limited | Administrative & support | 2008 |
| Fisk Investments Ltd | Real estate | 2024 |
| Fit&Flair Limited | Wholesale & retail | 2025 |
| Fitness Results Hub Limited | Wholesale & retail | 2026 |
| Fitters (Bromley) Limited | Extraterritorial | 2011 |
| Fitters (Edinburgh) Limited | Extraterritorial | 2011 |
| Fitters (Falkirk) Limited | Extraterritorial | 2011 |
| Fitters (Liverpool) II Ltd | Professional & scientific | 2018 |
| Fitters (Liverpool) Limited | Extraterritorial | 2011 |
| Fitters (Redcar) Limited | Extraterritorial | 2011 |
| Fitters (Wakefield) Limited | Extraterritorial | 2011 |
| Fitters (Workington) Limited | Extraterritorial | 2011 |
| Fitya Sports Club CIC | Education | 2025 |
| Fitzjohns Capital III LLP | | 2024 |
| Fitzjohns Dyce Nominees 1 Ltd | Professional & scientific | 2024 |
| Fitzjohns Dyce Nominees 2 Ltd | Professional & scientific | 2024 |
| Five DOT Management Ltd | Real estate | 2025 |
| Five Star Inns Limited | Hospitality | 1964 |
| Five Star Store Limited | Wholesale & retail | 2017 |
| Fivefourstudios Limited | Professional & scientific | 2014 |
| Fivestar Finance Limited | Extraterritorial | 2016 |
| Fivestar Logistics and Moving Services Limited | Transport & logistics | 2023 |
| Fiveway Corporate Limited | Other services | 2019 |
| FIX Your Bills Limited | Other services | 2014 |
| Fixfast Construction Ltd | Construction | 2025 |
| FKL Driver Limited | Other services | 2018 |
| Flackford Ltd | Extraterritorial | 2014 |
| Flagship Brands Ltd | Wholesale & retail | 2005 |
| Flaircourt Properties Limited | Real estate | 1964 |
| Flat Iron Company Limited | Real estate | 1998 |
| Flatoutsimulations Limited | Information & communication | 2017 |
| Flavius Angelo Vans & Cars Ltd | Wholesale & retail | 2023 |
| Flavour Shawarma Salford Ltd | Hospitality | 2023 |
| Flesh - Circle Square Ltd | Other services | 2026 |
| Flexible Industrial Solutions Ltd | Professional & scientific | 2026 |
| Flexidepot UK Ltd | Transport & logistics | 2025 |
| Fleximax Ltd | Arts & recreation | 2023 |
| Flexisaf Ltd | Information & communication | 2023 |
| Flight Claim Service Ltd | Other services | 2025 |
| Flintstone Corporation Ltd | Real estate | 2014 |
| Flipboard UK Limited | Information & communication | 2012 |
| Flixton Road Management Ltd | Real estate | 2026 |
| FLO Serrvices Ltd | Administrative & support | 2025 |
| Flojir Limited | Real estate | 2023 |
| Flomak Elegance Ltd | Hospitality | 2019 |
| Floodjack International Limited | Construction | 2015 |
| Floor Fitters Manchester Ltd | Construction | 2022 |
| Flora and Essence Ltd | Manufacturing | 2026 |
| Flora Global Trading Ltd | Wholesale & retail | 2025 |
| Flora Interior Design Ltd | Manufacturing | 2024 |
| Floral Prop Hire Limited | Administrative & support | 2013 |
| Florence 12 Ltd | Real estate | 2025 |
| Florin Enterprises Ltd | Extraterritorial | 2004 |
| Florin the Painter Ltd | Construction | 2024 |
| Flourish Care Solutions Ltd | Health & social care | 2024 |
| Flow UK Real Estate Holdings Limited | Real estate | 2020 |
| FLOW4WARD CIC | Education | 2025 |
| Flowers Stone UK Ltd | Wholesale & retail | 2024 |
| Flunet Ltd | Construction | 2026 |