| Anju Design Limited | Professional & scientific | 1998 |
| Anosia Biotechnologies Limited | Extraterritorial | 2019 |
| Anticipatory Health Limited | Information & communication | 2014 |
| AP Trims Ltd | Manufacturing | 2026 |
| Apexcrestgroup Ltd | Wholesale & retail | 2026 |
| Apis Films Limited | Information & communication | 1999 |
| Apostle Electrical & Automation Limited | Construction | 2018 |
| Archies Campers Ltd | Wholesale & retail | 2021 |
| Argent (Clothing) Limited | Wholesale & retail | 1973 |
| Arithmo Accountancy Limited | Professional & scientific | 2015 |
| Artificial Intelligence and Data Consulting Limited | Professional & scientific | 2024 |
| Ashe Green Civil Engineers Limited | Construction | 2008 |
| Ashford Demo Waste Recycling Limited | Other services | 2010 |
| ASL Property Services Ltd | Real estate | 2004 |
| Asphalt Supervision Services Limited | Construction | 2000 |
| Aspinall Services Ltd | Households | 2019 |
| Aspire Goldcrest Homes Ltd | Real estate | 2022 |
| Aspire Goldcrest Ltd | Construction | 2020 |
| Aspired Talent Ltd | Administrative & support | 2024 |
| Assimilate Systems Ltd. | Information & communication | 2013 |
| ATD Properties Norfolk Ltd | Construction | 2021 |
| Athena Autos Limited | Financial services | 2017 |
| Athiran UK Limited | Wholesale & retail | 2022 |
| Atticus Agency Ltd | Professional & scientific | 2022 |
| Attleborough Vets Limited | Professional & scientific | 2025 |
| Aubrey Hawkins Limited | Construction | 2011 |
| Auction to Amazing Ltd | Real estate | 2026 |
| Auctionstoamazing Ltd | Real estate | 2026 |
| Auditpath Ltd | Professional & scientific | 2025 |
| Audur Vesteins Ltd | Professional & scientific | 2016 |
| Auto Body Repair Group Limited | Wholesale & retail | 2023 |
| Autoglo UK Ltd | Administrative & support | 2025 |
| Avena Environmental Limited | Water & waste | 2010 |
| Avena Holdings Limited | Financial services | 2023 |
| Avena Innovations Ltd | Water & waste | 2021 |
| Aventura Trading Ltd | Financial services | 2025 |
| Aviation Consulting Limited | Professional & scientific | 2023 |
| Aviation Tool Supplies Limited | Manufacturing | 2017 |
| AW Control Solutions Limited | Professional & scientific | 2018 |
| Awesome Spices Ltd | Wholesale & retail | 2020 |
| B & B Telecommunications Ltd | Information & communication | 2019 |
| B M J (Services) Limited | Real estate | 2001 |
| Backyard Alpacas Ltd | Agriculture & fishing | 2024 |
| Badger Flooring Ltd | Construction | 2023 |
| Balance ICT Limited | Information & communication | 2014 |
| Balanus Assets Limited | Financial services | 2012 |
| Bamboo NR19 UK Ltd | Hospitality | 2026 |
| Bamf TM Ltd | Construction | 2025 |
| Banner Roofing Services Ltd | Construction | 2025 |
| Banson Decorators Ltd | Construction | 2002 |
| Bardell Auto's Limited | Wholesale & retail | 2015 |
| Barkers Farm Developments Ltd | Construction | 2021 |
| Barnes Print (East Anglia) Limited | Manufacturing | 2010 |
| Barrett Window Cleaning Services Ltd | Other services | 2013 |
| Battley Marine Ltd. | Manufacturing | 1978 |
| BC Safety Solutions Ltd | Professional & scientific | 2025 |
| Bclt Holdings Ltd | Financial services | 2024 |
| Bcsurveys Ltd | Information & communication | 2019 |
| BDC Scaffolding Ltd | Construction | 2014 |
| BE More Agile Ltd | Information & communication | 2018 |
| Beast Coast Merchandise Ltd | Manufacturing | 2025 |
| Beauty NOW (2006) Ltd | Other services | 2018 |
| BEECHGROVE1 Ltd | Real estate | 2025 |
| Beehive Staging Ltd | Construction | 2019 |
| Begley Electrical Installations Ltd | Construction | 2021 |
| Belmont Gore Ltd | Agriculture & fishing | 2016 |
| Benchmark Domcare Services Ltd | Administrative & support | 2020 |
| BFP Fish Selling Company Limited | Wholesale & retail | 1975 |
| BHW Creative Ltd | Information & communication | 2016 |
| Big Dog Consultancy Ltd | Administrative & support | 2005 |
| Big White Duck Company Ltd | Hospitality | 2012 |
| Billingford Lakes Limited | Agriculture & fishing | 2018 |
| Billionz Barber Ltd | Other services | 2025 |
| Biloba Properties Ltd | Real estate | 2025 |
| Binkyboo the First Ltd | Transport & logistics | 2023 |
| Bins Group Ltd | Water & waste | 2020 |
| Binsco Ltd | Administrative & support | 2022 |
| Birds Building & Roofing Ltd | Construction | 2018 |
| Bishy Barnabees Day Nursery Limited | Education | 2008 |
| BJD Holdings Limited | Administrative & support | 2017 |
| Black Cat Coffee Limited | Administrative & support | 2021 |
| Black Tower Games Ltd | Wholesale & retail | 2021 |
| Blackmore Dalhanyk Associates Ltd | Professional & scientific | 2015 |
| Bloomfield Biomechanics Limited | Health & social care | 2024 |
| Blue JAY Meadery Ltd | Wholesale & retail | 2022 |
| Blue Tile Health Ltd | Public administration | 2024 |
| Bluebell Square Limited | Real estate | 2011 |
| Bluebox Storage and Warehousing Ltd | Households | 2022 |
| Bluevoice Ltd | Other services | 2013 |
| Blundell Commercial Lettings Limited | Real estate | 2026 |
| Blundell Lettings Ltd | Real estate | 2023 |
| BM Complete Cleaning Services Limited | Administrative & support | 2020 |
| BMS Spa's Ltd | Other services | 2019 |
| BOB and Dots Cottages Ltd | Hospitality | 2023 |
| Boho Flower Design Ltd | Manufacturing | 2022 |
| Boiler Upgrade Ltd | Construction | 2023 |
| Bombay Dereham Ltd | Hospitality | 2024 |
| Bonners Plumbing and Heating Limited | Construction | 2017 |
| Borrow Hall Farm Ltd | Agriculture & fishing | 2014 |
| BPS (Norwich) Limited | Construction | 2026 |