| F D Mclean Decorators Limited | Administrative & support | 2011 |
| F R Estate Limited | Households | 1954 |
| F&C Advisory Services Limited | Professional & scientific | 2025 |
| F&CS1 Ltd | Hospitality | 2021 |
| F&M Hygiene and Therapy Ltd | Administrative & support | 2019 |
| F&M Management Co Limited | Real estate | 2025 |
| F&T Consulting Ltd | Information & communication | 2025 |
| F.A.D. Rusu Ltd | Construction | 2017 |
| F.Khan Ltd | Financial services | 2019 |
| F.M. Optometric Services Limited | Health & social care | 2004 |
| F.M.S.L Ltd | Wholesale & retail | 2024 |
| F.N.L. Logistics Limited | Transport & logistics | 2013 |
| F.Ryn Ltd | Construction | 2021 |
| F1GURE Ltd | Professional & scientific | 2023 |
| F5CS Ltd | Wholesale & retail | 2013 |
| F77 Ltd | Wholesale & retail | 2026 |
| FAB Flowers Limited | Wholesale & retail | 2010 |
| FAB Sales and Marketing Ltd | Wholesale & retail | 2020 |
| Fabamin Limited | Financial services | 2021 |
| Fabric Design Studio Ltd | Wholesale & retail | 2026 |
| Fabrick X Ltd | Real estate | 2024 |
| Fabrielle Limited | Health & social care | 2011 |
| Fabriq Limited | Construction | 2019 |
| Fabrista Textile Ltd | Wholesale & retail | 2025 |
| Fabs Limited | Real estate | 2009 |
| Fabulous Finishes UK Ltd | Construction | 2022 |
| Facades Build Services Ltd | Construction | 2021 |
| Facciavista Brickwork Ltd | Construction | 2021 |
| Face by U Ltd | Health & social care | 2023 |
| Face Lace Limited | Wholesale & retail | 2011 |
| Face London Ltd | Wholesale & retail | 2019 |
| Fades Hair Studio Limited | Other services | 2015 |
| Fadi Brave Cleaning Ltd | Administrative & support | 2024 |
| Fahmaz Holdings Limited | Financial services | 2025 |
| Fahmaz Investments Ltd | Financial services | 2016 |
| Fahmaz Properties Limited | Real estate | 2014 |
| Fahmm Investments Ltd | Real estate | 2025 |
| FAI Motors Ltd | Wholesale & retail | 2024 |
| Faiblosco Ltd | Health & social care | 2015 |
| Fair Concept Limited | Hospitality | 2017 |
| Fair Deals Trader Ltd | Wholesale & retail | 2019 |
| Faircare Ltd | Health & social care | 2022 |
| Fairdeal Homes Limited | Real estate | 2006 |
| Fairfield Estate Agents Limited | Real estate | 1996 |
| Fairfield Investment Property Ltd | Real estate | 2022 |
| Fairfield Lettings Ltd | Real estate | 2014 |
| Fairglow Investment Limited | Real estate | 2025 |
| Fairmay Investment Corporation Limited | Real estate | 2005 |
| Fairoaks Holdings Limited | Financial services | 2023 |
| Fairoaks Properties Limited | Real estate | 2023 |
| Fairquid Limited | Information & communication | 2015 |
| Fairview Health Limited | Wholesale & retail | 2009 |
| Fairview Health Partnerships Limited | Wholesale & retail | 2010 |
| Fairview Lettings & Trading Ltd | Hospitality | 2016 |
| Fairview Pharmacy Limited | Health & social care | 2010 |
| Fairway Commerce Limited | Financial services | 2019 |
| Fairway Design & Build Limited | Construction | 2023 |
| Fairway Global Consultants Ltd | Professional & scientific | 2025 |
| Fairway Properties UK LLP | | 2008 |
| Fairydell Management Company Limited | Households | 2022 |
| Faisal of London Limited | Other services | 2002 |
| Faith Engaged Ltd | Extraterritorial | 2010 |
| Faith Wellness Ltd | Health & social care | 2025 |
| Faizbit Ltd | Information & communication | 2011 |
| FAJ Limited | Administrative & support | 2007 |
| Falafel & Shawarma Lebaness Ltd | Hospitality | 2014 |
| Falafel Bar Harrow Ltd | Hospitality | 2017 |
| Falafel Bar London Limited | Hospitality | 2017 |
| Falco Carpentry Limited | Manufacturing | 2021 |
| Falcon Abseiling Ltd | Construction | 2016 |
| Falcon Autos Ltd | Wholesale & retail | 2016 |
| Falcon Capital Investments Ltd | Financial services | 2023 |
| Falcon Courier Service Ltd | Wholesale & retail | 2024 |
| Falcon Electrical Contractors Ltd | Construction | 2019 |
| Falcon House Properties Ltd | Construction | 2018 |
| Falcon House to Home Limited | Construction | 2013 |
| Falcon Investments and Finance Limited | Real estate | 2017 |
| Falconocean Limited | Wholesale & retail | 1991 |
| Faldu Holdings Ltd | Real estate | 2021 |
| Falindos Investment & Trading Limited | Financial services | 2024 |
| Falkirk Data Services Limited | Information & communication | 2025 |
| Falkon One Ltd | Real estate | 2024 |
| Fallback Rentals Ltd | Information & communication | 2024 |
| Fame Group Ltd | Financial services | 2024 |
| Fame Project Ltd | Construction | 2026 |
| Fameh Ltd | Real estate | 2018 |
| Famesoft Limited | Real estate | 1988 |
| Families in Action Together Ltd | Health & social care | 2022 |
| Family and Friend Estate Ltd | Real estate | 2023 |
| Family Eyecare Limited | Wholesale & retail | 1993 |
| Family GP Medical Services Limited | Health & social care | 2023 |
| Famous Catering Ltd | Hospitality | 2025 |
| Famous Fast Food Ltd | Hospitality | 2025 |
| Famous Shaworma Ltd | Hospitality | 2025 |
| Famous Textile UK Ltd | Wholesale & retail | 2023 |
| Fana Limited | Wholesale & retail | 2022 |
| Fancy Bambino Ltd | Other services | 2025 |
| Fandam Limited | Real estate | 2024 |
| Fandamental Ltd | Professional & scientific | 2021 |
| Fane Drylining Ltd | Construction | 2022 |