| 24MACX Ltd | Wholesale & retail | 2023 |
| 2MCUBED Ltd | Professional & scientific | 2016 |
| 30C Property Limited | Real estate | 2017 |
| 45 Fuel Limited | Hospitality | 2026 |
| 59 Eastdown Park Limited | Real estate | 2002 |
| 7C Northbrook Road Limited | Administrative & support | 2018 |
| A & N Perkins Limited | Manufacturing | 2004 |
| A & T Computers Limited | Information & communication | 1998 |
| A a U Limited | Manufacturing | 2002 |
| A Wonderful Life Limited | Other services | 2017 |
| A&C Garden Services Limited | Administrative & support | 2016 |
| A&P Irrigation Limited | Water & waste | 2019 |
| A&V Logistics Ltd | Transport & logistics | 2017 |
| Abla Evjeg Consultants Limited | Professional & scientific | 2023 |
| AC Developments (Norfolk) Ltd | Construction | 2025 |
| Accounting Digital Ltd | Professional & scientific | 2021 |
| Achieve Arts Agency Limited | Arts & recreation | 2021 |
| Across the Board (EA) Ltd | Education | 2026 |
| ACS (EYE) Properties Ltd | Real estate | 2023 |
| Activate INS Limited | Financial services | 2023 |
| Acutech Precision Engineering Limited | Manufacturing | 2016 |
| ADAPT4LIFE Limited | Construction | 2025 |
| Adira Events and Courses Ltd | Arts & recreation | 2021 |
| Adira Performance Ltd | Arts & recreation | 2018 |
| Agripro Trading Limited | Wholesale & retail | 2026 |
| AHK Healthcare Limited | Health & social care | 2020 |
| Airport Direct Ltd | Transport & logistics | 2016 |
| AJB Estates Ltd | Real estate | 2014 |
| AJB Telecoms Consultancy Ltd | Information & communication | 2020 |
| AJF Site Services Ltd | Manufacturing | 2010 |
| ALB Coaching Ltd | Health & social care | 2025 |
| Alder Carr Consultants Limited | Administrative & support | 2012 |
| Aline Developments Ltd | Construction | 2019 |
| ALL Sporting Events Ltd | Arts & recreation | 2023 |
| ALL the Feels Collective Limited | Arts & recreation | 2018 |
| Allisons Farm Management Company Limited | Households | 2022 |
| Aluco Advisers Limited | Professional & scientific | 2013 |
| AM Kirk Holdings Limited | Financial services | 2025 |
| Amacan Limited | Wholesale & retail | 2013 |
| Amalfie Holdings Limited | Financial services | 2026 |
| Amazon Leisure (UK) Limited | Arts & recreation | 1999 |
| Amis & Ward Development Ltd | Construction | 2025 |
| Amoghasiddhi Buddhist Centre | Education | 2003 |
| Amor Street Food Ltd | Hospitality | 2024 |
| AMY Rose Aesthetics Limited | Other services | 2024 |
| Anchor Window Systems Limited | Wholesale & retail | 1993 |
| Anct Ltd | Real estate | 2026 |
| Anderson Wray Ltd | Professional & scientific | 2011 |
| Andreassen Technologies Ltd | Information & communication | 2025 |
| Andrew Westby Consulting Ltd | Professional & scientific | 2025 |
| Andy Free Ltd | Health & social care | 2013 |
| Anglian Bolts & Consumables Ltd | Wholesale & retail | 2020 |
| Anglian Demolition & Asbestos Limited | Construction | 2005 |
| Anglian Demolition Group Limited | Extraterritorial | 2019 |
| Anglian Demolition Limited | Extraterritorial | 2019 |
| Anglian Metal Recycling Limited | Extraterritorial | 2019 |
| Anglian Plant & Recycling Limited | Construction | 2009 |
| Anglian Poultry Services Ltd | Administrative & support | 2010 |
| Anglian Properties Limited | Construction | 2017 |
| Anglian Scaffolding Group Limited | Extraterritorial | 2019 |
| Anglian Skip Hire Limited | Extraterritorial | 2021 |
| Anglian Waste Recycling Group Limited | Financial services | 2019 |
| Ango Vilia Limited | Hospitality | 2021 |
| ANN & Ezra Ltd | Wholesale & retail | 2025 |
| Anna BYE Ltd | Professional & scientific | 2021 |
| Anrpr Limited | Professional & scientific | 2023 |
| Anthony Marett Consultants Ltd | Professional & scientific | 2018 |
| Antoinette Aesthetics Ltd | Water & waste | 2022 |
| AP Leadership Group Ltd | Education | 2023 |
| APO Norfolk Ltd | Other services | 2026 |
| Apollo Group (Norfolk) Ltd | Administrative & support | 2023 |
| Aquatics Café Limited | Hospitality | 2024 |
| Arabella Stagg Limited | Real estate | 2023 |
| Aran's Space Limited | Health & social care | 2026 |
| Arco Safety Ltd | Administrative & support | 2025 |
| ARD Consulting Engineers Ltd | Professional & scientific | 2022 |
| Armeria Floral Design Ltd | Wholesale & retail | 2025 |
| Arpels Group Ltd | Education | 2016 |
| Arpels Intel Ltd | Professional & scientific | 2026 |
| ARS (Attleborough Roofline Services) Ltd | Construction | 2025 |
| ASH Building and Maintenance (Norfolk) Limited | Construction | 2019 |
| ASH Manufacturing (Services) Limited | Manufacturing | 2010 |
| ASH Manufacturing Limited | Manufacturing | 2010 |
| Associated Musical Services Limited | Arts & recreation | 1994 |
| Association of Christian Writers | Other services | 1998 |
| Attleborough Developments Ltd | Real estate | 2010 |
| Attleborough Industrial Property Ltd | Real estate | 2013 |
| Attleborough Motor Works Limited | Administrative & support | 1946 |
| Attleborough Plumbing Services Ltd | Construction | 2015 |
| Attleborough Service Centre (Norfolk) Limited | Wholesale & retail | 2016 |
| Attleborough Snooker Centre Limited | Hospitality | 2014 |
| Attleborough Town Social Club C.I.C. | Hospitality | 2025 |
| Auber Electrical Ltd | Construction | 2019 |
| Autoscot Limited | Professional & scientific | 2026 |
| Avendale Lettings Limited | Real estate | 2021 |
| Aviation Technical Services Ltd | Manufacturing | 2025 |
| Azure Bars Ltd | Hospitality | 2022 |
| B W Drewery Limited | Wholesale & retail | 2008 |
| B11 Education Ltd | Education | 2010 |
| B4 Car Network Limited | Wholesale & retail | 2003 |