| 24 Mortgage & Financial Services Limited | Financial services | 2024 |
| 24/7HEATING&PLUMBING.SOLUTIONS Ltd | Construction | 2018 |
| 26 Watton Ltd | Real estate | 2013 |
| 3 Bro's Crossfit Ltd | Arts & recreation | 2021 |
| 3-6 Old Allotment Close Management Company Limited | Households | 2017 |
| 3118 Creative Ltd | Professional & scientific | 2026 |
| 3D Instruments Limited | Professional & scientific | 1992 |
| 3DI Power Limited | Professional & scientific | 1999 |
| 3M Multi-Task Ltd | Construction | 2018 |
| 4 Secure Self-Storage Limited | Real estate | 2014 |
| 453SPACE Ltd | Wholesale & retail | 2025 |
| 4D Holdings Ltd | Professional & scientific | 2019 |
| 4D Strategic Systems Ltd | Information & communication | 2026 |
| 4TADA Limited | Transport & logistics | 2024 |
| 5 Stone Properties Ltd | Construction | 2019 |
| 50 50 Holdings Limited | Wholesale & retail | 2018 |
| 7 Pecados Rurais Ltd | Hospitality | 2023 |
| 7PROS Limited | Wholesale & retail | 2016 |
| A E Rentals Group Ltd | Real estate | 1966 |
| A F Machinery (Holdings) Limited | Financial services | 2025 |
| A J Collins Limited | Administrative & support | 2002 |
| A K Barber Services Limited | Other services | 2020 |
| A P Tech Ltd | Arts & recreation | 2024 |
| A R Y Enterprises Ltd | Transport & logistics | 2023 |
| A&M Multisports and Performing Arts LLP | | 2016 |
| A. F. Machinery Limited | Agriculture & fishing | 1990 |
| A.G.A. Group Consultancy Limited | Other services | 2018 |
| A.P. (East Anglia) Limited | Manufacturing | 1997 |
| A11 Medical Services Ltd | Education | 2019 |
| AA Electrical Engineering Ltd | Manufacturing | 2024 |
| AA Storage Solutions Ltd | Administrative & support | 2023 |
| AAB MAX Ltd | Wholesale & retail | 2022 |
| AAC Technical Services Limited | Administrative & support | 2012 |
| Abbey Barns Thetford Management Company Limited | Households | 2015 |
| Abbey Fire & Security Ltd | Construction | 2021 |
| Abbey Fire Doors Ltd | Administrative & support | 2009 |
| Abbey Fire Stopping Ltd | Extraterritorial | 2026 |
| Abbey Group Holdings Ltd | Professional & scientific | 2020 |
| Abbey Race Engineering Ltd | Wholesale & retail | 2025 |
| Abbeygate IT Solutions Ltd | Information & communication | 2021 |
| Abel Construction Ltd | Construction | 2019 |
| Abel Developments Limited | Construction | 2007 |
| Abel Energy Limited | Administrative & support | 2025 |
| Abel Holdings (Norfolk) Limited | Professional & scientific | 2013 |
| Abel Homes Limited | Construction | 1987 |
| Abel Properties Limited | Real estate | 1962 |
| Able Cleaning & Hygiene Supplies Ltd | Wholesale & retail | 2020 |
| Academy Close Management Company Limited | Households | 2022 |
| Academy of Clinical Mastery Limited | Manufacturing | 2024 |
| Access Training (UK) | | 1997 |
| Accord LUX Ltd | Transport & logistics | 2019 |
| Acer Logistics Ltd | Transport & logistics | 2026 |
| Acharya Mentoring Ltd | Education | 2022 |
| Acharya Resources Ltd | Information & communication | 2025 |
| Acorn Change Management Limited | Information & communication | 2016 |
| Acorn Taxis Thetford Ltd | Administrative & support | 2019 |
| Active Circle Ltd | Real estate | 2024 |
| Actuator Repair Services Limited | Manufacturing | 2014 |
| Acumen CNC Ltd | Manufacturing | 2017 |
| Adam’S Accommodation Limited | Hospitality | 2024 |
| Adelamead Ltd. | Extraterritorial | 2007 |
| ADG Publishing Ltd | Information & communication | 2009 |
| ADL Maintenance Contractor Ltd | Construction | 2022 |
| Admirals House Ltd | Hospitality | 2014 |
| Admoveo Holdings Ltd | Financial services | 2022 |
| Advanced Air (UK) Limited | Manufacturing | 1973 |
| Advanced Animal Health Limited | Agriculture & fishing | 2005 |
| Advanced Rack Inspections Ltd | Construction | 2025 |
| Advatech Limited | Manufacturing | 2000 |
| AFR Cleaning Services Limited | Administrative & support | 2005 |
| AFS Halal Resturant Ltd | Hospitality | 2023 |
| AFS Supplies Limited | Wholesale & retail | 1975 |
| AFS Technology Ltd | Wholesale & retail | 2025 |
| After the Antique Limited | Manufacturing | 1996 |
| Afterglow Tanning & Beauty Rooms Ltd | Other services | 2025 |
| AG DJ Brown Forestry Contractors Limited | Agriculture & fishing | 2023 |
| Ag-Automatic Ltd | Wholesale & retail | 2019 |
| AGA Group Enviro-Fix Limited | Professional & scientific | 2018 |
| Aimond Ltd | Construction | 2023 |
| AL4TRA Ltd | Transport & logistics | 2024 |
| Alan Lear Limited | Wholesale & retail | 2016 |
| Alby Estates Cleaning Limited | Households | 2019 |
| Alec James Ltd | Real estate | 2022 |
| Aless Fast Trans Limited | Transport & logistics | 2019 |
| Alfa Rentals Ltd | Administrative & support | 2026 |
| Alfred Heading & Sons Limited | Agriculture & fishing | 1954 |
| Align Automotive Ltd | Wholesale & retail | 2025 |
| Allhallows Consulting Ltd | Professional & scientific | 2013 |
| Alliance Homes Ltd | Administrative & support | 2010 |
| Alpa Wall Print Ltd | Manufacturing | 2024 |
| Alpha (UK) Enterprise Ltd | Real estate | 2014 |
| Alpha Property Consultants Ltd | Real estate | 2014 |
| Alpha Property Management and Services Limited | Construction | 2014 |
| Alpha Real Estate Development Ltd | Real estate | 2016 |
| ALT Precision Ltd | Manufacturing | 2024 |
| AM &SJ Services Ltd | Construction | 2026 |
| AM (EN) Distribution Limited | Transport & logistics | 2016 |
| AM Catering Ltd | Hospitality | 2018 |
| Amantoni Ltd | Construction | 2022 |
| Amas Investments Limited | Administrative & support | 2015 |