| Fivetreasures Limited | Extraterritorial | 2023 |
| Fix&Shine Limited | Administrative & support | 2025 |
| Fixit Commercials Ltd | Construction | 2025 |
| Fixit Roofcare Ltd | Construction | 2024 |
| Fixzie Group Ltd | Construction | 2020 |
| Fizza VERSE.313 Limited | Wholesale & retail | 2025 |
| Fizza's Boutique Limited | Wholesale & retail | 2025 |
| FJG Garages Limited | Wholesale & retail | 2022 |
| FK Pharma Limited | Health & social care | 2014 |
| Flag Motors Limited | Wholesale & retail | 2015 |
| Flame & Bear Limited | Other services | 2024 |
| Flame and Freeze DI Dolce Ltd | Hospitality | 2023 |
| Flame Retardant Polythene Limited | Professional & scientific | 2010 |
| Flame Risk Safety Solutions Limited | Professional & scientific | 2001 |
| Flame WOK Ltd | Hospitality | 2026 |
| Flameproofing (Europe) Limited | Manufacturing | 2014 |
| Flameproofings Limited | Manufacturing | 1995 |
| Flamesafe Compliance Ltd | Administrative & support | 2026 |
| Flash Homes Ltd | Real estate | 2025 |
| Flash Price Ltd | Wholesale & retail | 2018 |
| Flashfreak Limited | Transport & logistics | 2026 |
| Flat Glass and Glazing Limited | Construction | 2012 |
| Flavas 786 Ltd | Hospitality | 2025 |
| Flavour Burstz Ltd | Hospitality | 2022 |
| Flavour Takeaway Ltd | Hospitality | 2025 |
| Flavourpalace Ltd | Hospitality | 2021 |
| Flavours House Ltd | Hospitality | 2024 |
| Flavours N Spices Limited | Hospitality | 2019 |
| Flavourush Ltd | Hospitality | 2025 |
| Flawless Bargains Ltd | Wholesale & retail | 2017 |
| Flawless Hair and Beauty Lounge Limited | Other services | 2011 |
| Flawless Tanning & Beauty Limited | Other services | 2017 |
| Flebro Limited | Real estate | 1947 |
| Flectus IV Limited | Professional & scientific | 2025 |
| Fledglings Online CIC | Wholesale & retail | 2025 |
| Fleet Service Limited | Wholesale & retail | 2001 |
| Fleetgate Hardware Limited | Wholesale & retail | 2013 |
| Fleetgold Consulting Ltd | Administrative & support | 2007 |
| Fleetwood Leisure Ltd | Hospitality | 2024 |
| Fletcher Clarke Ltd | Real estate | 2025 |
| Fletcher CRE Ltd | Real estate | 2012 |
| Fletcher Taylor Ltd | Professional & scientific | 2017 |
| Fletcher Valentine Ltd | Administrative & support | 2022 |
| Fletchers Auto Valet Ltd | Wholesale & retail | 2025 |
| Fletchers Autocar Group Ltd | Wholesale & retail | 2025 |
| Fletchers Distribution Group Limited | Wholesale & retail | 2025 |
| Fletchers Hospitality Limited | Hospitality | 2026 |
| Flex Academy of Performing Arts Limited | Education | 2021 |
| Flex Luthor Limited | Information & communication | 2005 |
| Flex Padel Limited | Arts & recreation | 2026 |
| Flex Rental Properties Limited | Real estate | 2023 |
| Flexi Accounting Solutions Ltd | Professional & scientific | 2017 |
| Flexi Freegan Limited | Wholesale & retail | 2023 |
| Flexi Healthcare Ltd | Health & social care | 2022 |
| Flexible Security Solutions Limited | Other services | 2011 |
| Flexisense Ltd | Manufacturing | 2022 |
| Flexiss Consultants Limited | Real estate | 2017 |
| FLH Limited | Real estate | 2019 |
| FLI Cuts Limited | Other services | 2017 |
| Flight Airline Ltd | Wholesale & retail | 2025 |
| Flightpath Advisory Ltd | Professional & scientific | 2026 |
| Flitcraft Limited | Manufacturing | 2017 |
| Flitcraft Timber Frame Limited | Extraterritorial | 2018 |
| Flix 'N' PIX Ltd | Other services | 2008 |
| FLO Centric Holdings Limited | Professional & scientific | 2023 |
| FLO Lifestyle Limited | Wholesale & retail | 2025 |
| Flo-Apps Limited | Wholesale & retail | 2012 |
| Flocast Ltd | Information & communication | 2024 |
| Flokit Ltd | Professional & scientific | 2016 |
| Flol Limited | Information & communication | 2023 |
| Flook Tech Ltd | Information & communication | 2020 |
| Floor Co Group Ltd | Wholesale & retail | 2024 |
| Floor Design Contractors Limited | Construction | 1999 |
| Flooring Projects Limited | Construction | 2018 |
| Floors & Co Limited | Wholesale & retail | 2021 |
| Floors by Design Limited | Wholesale & retail | 2020 |
| Floranto Care Services Ltd | Health & social care | 2016 |
| Florenfield Ltd | Professional & scientific | 2012 |
| Florist Management and Consultancy Services Ltd | Information & communication | 2022 |
| FLORIST2FLORIST.COM Limited | Information & communication | 2002 |
| Flossstuff Ltd | Wholesale & retail | 2021 |
| Flourishcollectibles Limited | Manufacturing | 2024 |
| Flow Controls UK Limited | Wholesale & retail | 2009 |
| Flow Heat Plumbing & Heating Ltd | Construction | 2026 |
| Flow Inc Studios UN Ltd | Information & communication | 2021 |
| Flowclear Drainage Ltd | Professional & scientific | 2025 |
| Flower Takeaway Limited | Hospitality | 2024 |
| Flower. Catering Limited | Hospitality | 2025 |
| Flowersmiths Limited | Wholesale & retail | 2012 |
| Flowhack Limited | Information & communication | 2021 |
| Flowhesion Academies Trust C.I.C. | Education | 2019 |
| Flowstate of Mind Ltd | Wholesale & retail | 2024 |
| Flowtech Plastics Limited | Manufacturing | 2009 |
| Floxy Healthcare Ltd | Health & social care | 2025 |
| Fluent Lifetime Limited | Financial services | 2018 |
| Fluent Loans Limited | Financial services | 2009 |
| Fluent Money Limited | Financial services | 2007 |
| Fluent Mortgage Holdings Limited | Financial services | 2008 |
| Fluent Mortgages Limited | Financial services | 2006 |
| Fluffy Fluffy Liverpool Ltd | Hospitality | 2023 |