| Archie Williams & Co Ltd | Hospitality | 2020 |
| Architectural Ironmongery Limited | Extraterritorial | 2003 |
| Aristide Property Acquisitions Limited | Real estate | 2022 |
| ARM Complete Grounds Management & Maintenance Limited | Administrative & support | 2005 |
| ARP Associates Ltd | Professional & scientific | 2011 |
| Arrow House Limited | Real estate | 1971 |
| Art Works Exhibition Services Limited | Arts & recreation | 2012 |
| Arthomas Group Ltd | Professional & scientific | 2026 |
| Artisan Agencies Limited | Administrative & support | 2010 |
| Arts Abergavenny Community Interest Company | Administrative & support | 2020 |
| Aseado Cleaning Ltd | Administrative & support | 2026 |
| Ashe Green Associates Ltd | Professional & scientific | 2011 |
| Ashpoint Ltd | Real estate | 2019 |
| Astara Management Limited | Administrative & support | 2000 |
| Astra Broadband Group Limited | Information & communication | 2018 |
| Astrobel Property Limited | Real estate | 2015 |
| ATJ Sandblasting Ltd | Construction | 2025 |
| Atoz Drinks Limited | Wholesale & retail | 2020 |
| Auberge Bar & Restaurant Limited | Hospitality | 2012 |
| Authentic Paving Limited | Construction | 2015 |
| Aviation Support Consultancy Services Limited | Administrative & support | 2013 |
| AXY Ltd | Wholesale & retail | 2016 |
| B D Aber Limited | Hospitality | 2019 |
| B W Auto Services Ltd | Wholesale & retail | 2011 |
| Bace-Line Training Ltd | Administrative & support | 2021 |
| BAE Retail Limited | Professional & scientific | 2025 |
| Baileys Assets Ltd | Real estate | 2022 |
| Baileys DIY Limited | Wholesale & retail | 2012 |
| Baileys Property Holdings Limited | Real estate | 2020 |
| Baileys Wholesale Limited | Wholesale & retail | 2020 |
| Balance Sheet Talent Limited | Professional & scientific | 2025 |
| Balti Indian Limited | Hospitality | 2025 |
| Barker Information Management Solutions Ltd | Information & communication | 2019 |
| Barnes Plant Sales Ltd | Wholesale & retail | 2018 |
| Base Jump Logic Limited | Other services | 2024 |
| BDJ COX Properties Limited | Real estate | 2015 |
| BE More Strength and Conditioning Ltd | Education | 2024 |
| Beacon Getaways Ltd | Hospitality | 2018 |
| Beacon Search Ltd | Administrative & support | 2020 |
| Beacons Mobility Limited | Wholesale & retail | 2021 |
| Beacons Productions Ltd | Information & communication | 2016 |
| Bean & Bread Ltd | Hospitality | 2021 |
| Beatties Barbers NP7 Limited | Other services | 2015 |
| Beauty Central UK Limited | Health & social care | 2017 |
| Beechwood Car Care Ltd | Wholesale & retail | 2025 |
| Belle Community Hub CIC | Education | 2026 |
| Belmont House (Abergavenny) Limited | Health & social care | 2026 |
| BEN Marlog Training Ltd | Education | 2019 |
| Berg Homes Ltd | Construction | 2018 |
| Berti Ltd | Hospitality | 2025 |
| Bespoke & Oak Co. Ltd | Manufacturing | 2012 |
| Bethcar DP Ltd | Health & social care | 2018 |
| Bfitzpatrick Properties Ltd | Real estate | 2022 |
| BGD Consultancy Ltd | Information & communication | 2014 |
| Bhrr Limited | Wholesale & retail | 2021 |
| Bikeshed Communications Ltd | Professional & scientific | 2019 |
| BIM Consultants Ltd | Professional & scientific | 2018 |
| Biomax Fuels Ltd | Water & waste | 2006 |
| Bishops Bridge Properties Limited | Real estate | 2022 |
| Black FOX Flooring Ltd | Construction | 2019 |
| Black Mountain Gates Ltd | Manufacturing | 2022 |
| Black Mountain Ground Investigation Ltd | Professional & scientific | 2018 |
| Black Mountain Ventures Limited | Professional & scientific | 2004 |
| Black Mountains Circle Ltd | Wholesale & retail | 1997 |
| Black Mountains Marketing Ltd | Professional & scientific | 2023 |
| Blaenavon Garden Services Ltd | Other services | 2025 |
| Blaentrothy Limited | Administrative & support | 2000 |
| Blaze Environmental Ltd | Agriculture & fishing | 2021 |
| Bleep Communications Limited | Professional & scientific | 2011 |
| Bloomify Floristry Ltd | Wholesale & retail | 2023 |
| Blorenge Limited | Administrative & support | 2025 |
| Blue Chip Leasing Ltd | Administrative & support | 2022 |
| Blue Kite Trading Limited | Wholesale & retail | 2020 |
| Blue Wave Maritime Limited | Manufacturing | 2010 |
| Bluebells Forest Children Ltd | Education | 2026 |
| Border Counties Vintage Club Limited | Other services | 1998 |
| Border Country Creative Ltd | Information & communication | 2023 |
| Border Sawmill Ltd | Manufacturing | 2021 |
| Border Sundials Ltd | Manufacturing | 2015 |
| Bornfree Ltd | Other services | 2018 |
| Bossmans Retail Abergavenny Ltd | Wholesale & retail | 2025 |
| Bowen Building Contractors (Abergavenny) Limited | Construction | 2014 |
| Bowers Smith Property Services Limited | Real estate | 2024 |
| Bread & Honey Partners LLP | | 2015 |
| Brett Property Limited | Real estate | 2012 |
| Bretts Catering Limited | Hospitality | 2023 |
| BREW33 Ltd | Hospitality | 2026 |
| Brian Williams Enterprises Limited | Other services | 2020 |
| Briarwood Homes Limited | Real estate | 2023 |
| Brightspark Dog Training Ltd | Arts & recreation | 2019 |
| Brit-Stitch Limited | Manufacturing | 2012 |
| Bromfields Butchers Ltd | Wholesale & retail | 2015 |
| Brooks of Monmouth Limited | Other services | 2015 |
| BTH Property Marketing Services Limited | Professional & scientific | 2025 |
| Bubbles & Squeak Wellness Ltd | Manufacturing | 2024 |
| Builders Bitz Limited | Wholesale & retail | 2006 |
| Buildiq Limited | Information & communication | 2016 |
| Burton & Company (Property Lets) Ltd | Real estate | 2017 |
| BYE BYE Ocean Ltd | Information & communication | 2025 |
| C J Gibbons Limited | Wholesale & retail | 2016 |