| 4 Heat Limited | Construction | 2012 |
| 4WARD Loop Ltd | Information & communication | 2014 |
| 6 Montpelier Grove Limited | Households | 2007 |
| 7TH Heaven Kings Lynn Limited | Hospitality | 2018 |
| A B Equestrian, Fencing & Groundworks Limited | Administrative & support | 2014 |
| A G Landymore & SON Limited | Agriculture & fishing | 2014 |
| A. I. Management Limited | Real estate | 2012 |
| A. T. Vehicle Services Limited | Wholesale & retail | 2008 |
| A.D.S. Mobile Tyres Limited | Wholesale & retail | 2018 |
| A.M Blatch Electrical Contractors Ltd | Construction | 2001 |
| A10 Auto Centre Limited | Wholesale & retail | 2014 |
| A10 Pest Control Limited | Water & waste | 2004 |
| AA Brothers Restaurant Group Ltd | Hospitality | 2018 |
| Abbey Boilers & Heating Ltd | Construction | 2014 |
| ABI Building & Restoration Ltd | Construction | 2011 |
| ABY Solutions Limited | Information & communication | 2004 |
| Acess Property Developments Ltd | Construction | 2020 |
| Acorn Anaesthesia LLP | | 2024 |
| Acre Properties Limited | Real estate | 2025 |
| Active Telecoms Limited | Information & communication | 2003 |
| AD Meliora Academy Trust | Administrative & support | 2016 |
| Adelphi Homes Limited | Construction | 2015 |
| Adventure Fit Ltd | Professional & scientific | 2016 |
| After Today Partnership (Norfolk) Limited | Professional & scientific | 1994 |
| Ahimsa Plant Healing Community Interest Company | Wholesale & retail | 2018 |
| AHS (Norfolk) Limited | Construction | 2012 |
| Aime Education Ltd | Education | 2024 |
| Air Water Fish Ltd | Agriculture & fishing | 2020 |
| Alan Stockley & Company Limited | Wholesale & retail | 1961 |
| Alfred & Bear Ltd | Administrative & support | 2021 |
| Alfred Dodman & Co Limited | | 1897 |
| ALL Asphalt & Surfacing Limited | Construction | 2011 |
| Allweather Window Systems Limited | | 1987 |
| Ambassador Interiors (UK) Limited | Extraterritorial | 2008 |
| Ambit MHS Limited | Construction | 2013 |
| AMD Ventures Ltd | Real estate | 2024 |
| Amino Drinks Limited | Wholesale & retail | 2017 |
| Andrew's Hot Bread Shop Limited | Real estate | 1977 |
| Anglia Giving | Other services | 2002 |
| Anglia Television Ltd | Information & communication | 2023 |
| Anglian Automation Ltd | Administrative & support | 2021 |
| Anything Office Limited | Wholesale & retail | 2013 |
| AP Capital 222 Ltd | Professional & scientific | 2025 |
| ARK East Anglia Ltd | Construction | 2018 |
| Art Sales Limited | Education | 2024 |
| Arthur Wilson (Estates) Limited | Real estate | 1948 |
| Ashdown Electrical Services Limited | Wholesale & retail | 2007 |
| Ashley Read Property Management & Development Ltd | Real estate | 2018 |
| Ashley Todd Electrical Services Ltd | Energy | 2016 |
| Ashwood Lodge Farms Limited | Professional & scientific | 1959 |
| Aspires Limited | Health & social care | 1996 |
| Atech Motor Accessories Ltd | Manufacturing | 2021 |
| ATTENU8 Ltd | Information & communication | 2003 |
| Audika Ltd | Transport & logistics | 2019 |
| Audio Resolution Ltd | Professional & scientific | 2012 |
| AVN Arena Midlands Limited | Professional & scientific | 2014 |
| B & M (Project Management) Limited | Real estate | 1988 |
| B & R Plumbing and Property Maintenance Ltd | Construction | 2021 |
| Badger Publishing Limited | Education | 1989 |
| Badger Reading Boxes Limited | Education | 2009 |
| Balance Reformer Limited | Arts & recreation | 2025 |
| Banham Limited | Wholesale & retail | 2025 |
| Bank Farm Holdings Limited | Financial services | 2023 |
| Barrett Batchelor Mortgage Services LLP | | 2011 |
| Bawsey Developments Limited | Real estate | 2022 |
| Bbpod UK Ltd | Wholesale & retail | 2026 |
| Bc&R Car & Van Centre Ltd | Wholesale & retail | 2008 |
| Bc&R Holdings Ltd | Extraterritorial | 2015 |
| BE YOU UN Limited | Professional & scientific | 2020 |
| Bead Engineering Co. Limited | | 1972 |
| Bear Dent Ltd | Health & social care | 2014 |
| Beers of Europe Limited | Wholesale & retail | 2000 |
| Beeston Brewery Ltd | Manufacturing | 2005 |
| Belfast Linen Property Limited | Real estate | 1995 |
| Bella Warehouse Ltd | Hospitality | 2020 |
| Berkshire Printing Company Limited | Manufacturing | 1911 |
| Betaille & Co (Parasols) Ltd | Manufacturing | 2020 |
| Bethel Court Investments Ltd | Real estate | 2020 |
| Bethel Street Investments Ltd | Real estate | 2023 |
| Bexwell Estates Limited | Financial services | 2005 |
| BGG Estate Investment Ltd | Real estate | 2023 |
| Biddles Books Limited | Information & communication | 2013 |
| Billshrinker Ltd | Administrative & support | 2020 |
| BIO AG Limited | Real estate | 2018 |
| Bircham Estates Ltd | Hospitality | 2003 |
| Birdsall, Swash & Blackman Limited | Professional & scientific | 2007 |
| BIX Planning Limited | Professional & scientific | 2013 |
| BJ Groundworks Ltd | Construction | 2015 |
| BKL Projects Norfolk Ltd | Professional & scientific | 2016 |
| Black Forest Holdings Ltd | Financial services | 2025 |
| Blackline LV Consultancy Ltd | Professional & scientific | 2026 |
| Blackthorn Close (Heacham) Management Company Limited | Households | 2018 |
| Boolean Consulting Ltd | Extraterritorial | 2007 |
| Bowen Consultancy Ltd | Professional & scientific | 2021 |
| Brabble Limited | Information & communication | 2024 |
| Brancaster Staithe Sailing Club | Arts & recreation | 1991 |
| Brands-Uk.Co.Uk Ltd | Wholesale & retail | 2020 |
| Brighter Capability Limited | Professional & scientific | 2019 |
| Brighter Ways Norfolk CIC | Health & social care | 2023 |
| Brightstar Electrical Limited | Construction | 2008 |