| Fintel Services Limited | Financial services | 2002 |
| Fintel Support Limited | Other services | 2017 |
| Fir-Cone Limited | Real estate | 1994 |
| Fire House Spirits Ltd | Wholesale & retail | 2025 |
| Fire Protection BIM Services Ltd | Professional & scientific | 2021 |
| Fire-Safe (Assessors) Limited | Public administration | 2026 |
| Fireactiv Health and Wellbeing Ltd | Wholesale & retail | 2022 |
| Fired UP Corporation Limited | Manufacturing | 1996 |
| Firekite Limited | Information & communication | 2010 |
| Fireplace Factory Outlet Limited | Wholesale & retail | 2019 |
| Fireplace World (UK) Limited | Extraterritorial | 2003 |
| Firesolve Properties Limited | Real estate | 2017 |
| Firestop Systems (U.K.) Building Services Limited | Construction | 2006 |
| Firestop Systems (UK) Limited | Construction | 2002 |
| Firestop Systems Limited | Extraterritorial | 2009 |
| First 4 Lawyers Limited | Professional & scientific | 2008 |
| First Care Connect Ltd | Health & social care | 2026 |
| First Choice Property Investments Ltd | Real estate | 2014 |
| First Class Nursery ( Huddersfield) Limited | Education | 2012 |
| First Daily Care Ltd | Health & social care | 2026 |
| First Hand Express Ltd | Transport & logistics | 2025 |
| First in Education Ltd. | Education | 2014 |
| First Light Digital Marketing Ltd | Professional & scientific | 2026 |
| First of Four Media Ltd | Information & communication | 2026 |
| First Plus Medical Ltd | Health & social care | 2023 |
| First Stop Tyres (Rochdale) Ltd | Wholesale & retail | 2026 |
| First TEK Ltd | Real estate | 2025 |
| FIRST4HEALTHCARE Ltd | Health & social care | 2011 |
| FIRST4INJURYCLAIMS Limited | Administrative & support | 2021 |
| FIRST4LAWYERS Legal Services Limited | Administrative & support | 2015 |
| Firstbuy Shop Ltd | Wholesale & retail | 2026 |
| Firth Brothers Limited | Real estate | 1927 |
| Firth Gibbs Investments Limited | Real estate | 1954 |
| Firth House Properties Limited | Real estate | 2020 |
| Firth Process & Mechanical Ltd | Construction | 2015 |
| Firth Projects Limited | Administrative & support | 2011 |
| Firth Properties Group Ltd | Real estate | 2020 |
| Firth Tools Limited | Wholesale & retail | 2007 |
| Firtree Healthcare Limited | Health & social care | 2009 |
| Firwood Estates Limited | Real estate | 2002 |
| FIS Information Systems UK Limited | Information & communication | 2009 |
| Fish Roofing Ltd | Construction | 2013 |
| Fisher & Hirst Joinery Limited | Manufacturing | 2015 |
| Fisher Lewis Leisure Ltd | Other services | 2024 |
| Fisher Property and Accommodation Limited | Real estate | 2023 |
| Fishergate Hill Ltd | Health & social care | 2023 |
| FIT4FINANCE Limited | Manufacturing | 2011 |
| Fitness Connection (Mirfield) Ltd | Other services | 2023 |
| Fitness Education Ltd | Health & social care | 2023 |
| Fitness Online Direct Ltd | Wholesale & retail | 2012 |
| Fitzgerald Watch Company Ltd | Other services | 2024 |
| Five Rise Consultancy Ltd | Professional & scientific | 2016 |
| Five Rivers Insurance Solutions Ltd | Financial services | 2011 |
| Five Star Autocentre Limited | Wholesale & retail | 2009 |
| Five Star Triangle Limited | Other services | 2015 |
| Five Stars Consultancy Ltd | Education | 2024 |
| Fixbees Ltd | Education | 2013 |
| Fixby Healthcare Ltd | Health & social care | 2021 |
| Fixby Maths Tuition Ltd | Education | 2024 |
| Fixby Motors Ltd | Wholesale & retail | 2023 |
| Fixby Properties Ltd | Real estate | 2016 |
| Fixby Stores Limited | Extraterritorial | 2023 |
| Fixd Plumbing Ltd | Construction | 2023 |
| Fixwood Limited | Professional & scientific | 2017 |
| Fizspark Limited | Administrative & support | 2021 |
| Fizzywizzy Limited | Other services | 2024 |
| FJ Consultancy Ltd | Professional & scientific | 2020 |
| FK Capital Investments Limited | Financial services | 2023 |
| Flamebites Chicken Ltd | Hospitality | 2026 |
| Flames Balti & Pizza Base Ltd | Hospitality | 2019 |
| Flames House Ltd | Hospitality | 2023 |
| Flames Pizza Base Ltd | Hospitality | 2026 |
| Flamstop Holdings Limited | Financial services | 2015 |
| Flat Glass Equipment Limited | Wholesale & retail | 2012 |
| Flavor Impression Ltd | Hospitality | 2026 |
| Flavorlabs Ltd | Hospitality | 2025 |
| Flawless Flavours Limited | Hospitality | 2025 |
| Flawless Photography Group Limited | Administrative & support | 2023 |
| FLC Advisory Limited | Administrative & support | 2025 |
| Fleet and Asset Solutions Ltd | Extraterritorial | 2025 |
| Fleetcool Limited | Professional & scientific | 2020 |
| Fleetcool Software Limited | Information & communication | 2024 |
| Fleur & Grey Ltd | Wholesale & retail | 2015 |
| Flexi Sleep Ltd | Wholesale & retail | 2025 |
| Flexi-Therm Limited | Health & social care | 2024 |
| Flickers Lash Limited | Other services | 2021 |
| Flipnex Ltd | Wholesale & retail | 2026 |
| Floatology Ltd | Other services | 2019 |
| Flologik Solutions Limited | Administrative & support | 2025 |
| Floodsax Limited | Wholesale & retail | 2008 |
| Flooring Stars Ltd | Construction | 2021 |
| Flourish Accounting Ltd | Professional & scientific | 2020 |
| Flourish Childrens Services Limited | Health & social care | 2019 |
| Floury Ltd | Health & social care | 2015 |
| Flow Creative Communications Limited | Professional & scientific | 2014 |
| Flow Living Ltd | Real estate | 2026 |
| Flow Realty Ltd | Financial services | 2023 |
| Flow Solutions Group Limited | Transport & logistics | 2008 |
| Flower to the People Ltd | Professional & scientific | 2025 |
| Flowgold Limited | Administrative & support | 2024 |