| Finlayson Consultancy Ltd | Information & communication | 2019 |
| Finlink Ventures Ukeig | | 2002 |
| Finlinker Technology Limited | Information & communication | 2024 |
| Finn Aero Services Ltd | Manufacturing | 2026 |
| Finnovation Labs Limited | Other services | 2016 |
| Finnson Ltd | Wholesale & retail | 2020 |
| Finorient Ltd | Real estate | 2020 |
| Finquark Financial Technologies Limited | Wholesale & retail | 2025 |
| Fintek Marketing Limited | Other services | 2025 |
| Finweave Consulting Ltd | Professional & scientific | 2025 |
| FIP Industrial Limited | Construction | 2018 |
| Fire 'N Belly International Limited | Professional & scientific | 2009 |
| Fire Triangle Ltd | Administrative & support | 2018 |
| Firebird Stud Limited | Agriculture & fishing | 2009 |
| Firebrand Associates Limited | Professional & scientific | 2004 |
| Fired UP Pizza Ltd | Hospitality | 2017 |
| Firequacker Ltd | Hospitality | 2012 |
| Fireside Technology Consulting Ltd | Information & communication | 2025 |
| Firewire Limited | Wholesale & retail | 1997 |
| Firewise Supplies Limited | Wholesale & retail | 2005 |
| First Ascent Group Ltd | Professional & scientific | 1998 |
| First Cambridge Gateway Limited Partnership | | 2000 |
| First China International Economic Technology Co., Ltd | Wholesale & retail | 2023 |
| First Class Maintenance Ltd | Administrative & support | 2021 |
| First Climate Finance Limited | Professional & scientific | 2025 |
| First Copy IT Limited | Information & communication | 2003 |
| First Edition Translations Limited | Professional & scientific | 1990 |
| First Landing Education Limited | Administrative & support | 2014 |
| First National Oven Clean Ltd | Other services | 2025 |
| First Point Cleaning (Cambs) Limited | Administrative & support | 2019 |
| First Point Cleaning Service Limited | Administrative & support | 2019 |
| First Press ELT Limited | Information & communication | 2011 |
| First Press Limited | Arts & recreation | 2003 |
| First Press Property Investments Limited | Real estate | 2020 |
| First Principles Smartedu Ltd | Information & communication | 2024 |
| Firstchoice Construction Group Ltd | Construction | 2026 |
| Firstwhale Limited | Wholesale & retail | 2025 |
| Fish (Burwell) Limited | Wholesale & retail | 2011 |
| Fish Accounting & Translating Limited | Professional & scientific | 2018 |
| Fish Trade Ltd | Wholesale & retail | 2025 |
| Fishtail Productions Limited | Information & communication | 2014 |
| Fishvan Limited | Information & communication | 2016 |
| Fistreem International Limited | Manufacturing | 2004 |
| Fit Drive Ltd | Transport & logistics | 2025 |
| Fit for Purpose Quality Ltd | Professional & scientific | 2026 |
| Fitco Enterprise Limited | Wholesale & retail | 2020 |
| Fitflexiblefree Ltd | Health & social care | 2025 |
| Fitinvest Limited | Financial services | 2016 |
| Fitness Works Management Services Ltd | Real estate | 2008 |
| Fitork Group (UK) Limited | Wholesale & retail | 2026 |
| Fitting Nails Limited | Other services | 2019 |
| Fitzbillies (Cambridge) Limited | Wholesale & retail | 2011 |
| Fitzbillies Limited | Manufacturing | 2010 |
| Fitzgibbon & Associates Ltd | Professional & scientific | 2021 |
| Fitzwilliam College Developments Limited | Construction | 2025 |
| Fitzwilliam College Services Limited | Real estate | 1996 |
| Fitzwilliam Consulting Limited | Professional & scientific | 2005 |
| Fitzwilliam Court (Cambridge) Management Company Limited | Households | 1992 |
| Five AI Limited | Information & communication | 2016 |
| Five Alarm BIO Limited | Professional & scientific | 2016 |
| Five Cars Films Ltd | Information & communication | 2022 |
| Five Miles From Cambridge Limited | Real estate | 2012 |
| Five Rita Road Limited | Households | 2017 |
| Five Rita Road RTM Company Limited | Households | 2005 |
| Five Tribes Ltd | Other services | 2018 |
| FIX Fast Technologies Ltd | Information & communication | 2025 |
| FIX My Tyre Cambridge Ltd | Wholesale & retail | 2023 |
| FIX Recruitment Solutions Limited | Health & social care | 2013 |
| Fixbork Limited | Information & communication | 2016 |
| Fixed Point Media Limited | Professional & scientific | 2018 |
| Fixed Property Group Limited | Construction | 2026 |
| Fixedrate Plumbing Ltd | Construction | 2026 |
| Fixr Systems Limited | Professional & scientific | 2024 |
| Fizyka Ltd | Professional & scientific | 2025 |
| Fizz Limited | Hospitality | 2025 |
| FJX Trading Limited | Manufacturing | 2024 |
| FK Meghna Ltd | Hospitality | 2024 |
| Flack and Chapman Limited | Construction | 2017 |
| Flag FEN Power Limited | Manufacturing | 2021 |
| Flame & Crumb Limited | Hospitality | 2024 |
| Flames 301 Limited | Hospitality | 2025 |
| Flasch International Law Limited | Professional & scientific | 2023 |
| Flashatom Ltd | Extraterritorial | 2021 |
| Flashpoint Media Limited | Information & communication | 2002 |
| Flashtag Ltd | Information & communication | 2019 |
| Flaura Ltd | Professional & scientific | 2020 |
| Flavazmc Limited | Hospitality | 2025 |
| Flavour Station Ltd | Hospitality | 2018 |
| Flavour Works Limited | Hospitality | 2025 |
| Flavourful Richness Foods Ltd | Wholesale & retail | 2024 |
| Flaying ANT Ltd | Wholesale & retail | 2025 |
| Fleaglass Limited | Wholesale & retail | 2010 |
| Fleavintage Cambridge Limited | Wholesale & retail | 2024 |
| Fleek Events Ltd | Other services | 2025 |
| Fleet Supply Limited | Wholesale & retail | 2024 |
| Fleeyo Limited | Transport & logistics | 2022 |
| Fleot Limited | Professional & scientific | 2019 |
| Flex Dance Studios Ltd | Arts & recreation | 2021 |
| Flex Machina Ltd | Wholesale & retail | 2020 |
| Flexenable Technology Limited | Manufacturing | 2022 |