| Asterlavis Limited | Health & social care | 2024 |
| Astro Fabrications Ltd | Manufacturing | 2020 |
| Asuata Housing Limited | Real estate | 2023 |
| AT One NE Community Interest Company | Arts & recreation | 2024 |
| At&T Solutions Ltd | Manufacturing | 2023 |
| Ataraxia Engineering Ltd | Manufacturing | 2026 |
| Athena Supported Accommodation (North-East) Limited | Health & social care | 2018 |
| Athena Supported Accommodation (North-West) Limited | Hospitality | 2021 |
| ATI (NE) Ltd | Real estate | 2025 |
| ATK Engineering and Services Ltd | Professional & scientific | 2021 |
| Atkinson Developments (NE) Limited | Construction | 2025 |
| Atkinson Homes 66 Limited | Construction | 2025 |
| Atkinson Investments Ltd | Real estate | 2020 |
| Atkinson Property Group Limited | Real estate | 2025 |
| Atkinsons Electrical (NE) Limited | Construction | 2025 |
| Atlantic Project Services Limited | Professional & scientific | 2025 |
| Atlas Action CIC | Education | 2018 |
| Atlas Productions Ltd | Information & communication | 2024 |
| Atlas Theatre Company CIC | Arts & recreation | 2024 |
| ATLETICO70 Ltd | Hospitality | 2026 |
| Atomic Design & Consulting Limited | Professional & scientific | 2019 |
| ATR (NE) LLP | | 2024 |
| ATZ Mart Ltd | Wholesale & retail | 2025 |
| Aucto Visio Ltd | Arts & recreation | 2025 |
| Audio Arcade Ltd | Information & communication | 2023 |
| Audio Logistics VA Ltd. | Manufacturing | 2000 |
| Audlexa Ltd | Wholesale & retail | 2026 |
| Auraxcel Ltd | Wholesale & retail | 2025 |
| Aurelo Group Limited | Construction | 2026 |
| Autism Works Limited | Information & communication | 2010 |
| Autism-In-Mind Community Interest Company | Health & social care | 2015 |
| Auto Electrical Solutions Limited | Wholesale & retail | 2002 |
| Auto Sales North East Ltd | Wholesale & retail | 2020 |
| Autodidactic Limited | Administrative & support | 2003 |
| Automated Building Controls Ltd | Construction | 2021 |
| Automotive Finance Associates Ltd | Financial services | 2017 |
| Autopaints Sunderland Ltd | Wholesale & retail | 2019 |
| Autotune (Sunderland) Limited | Wholesale & retail | 2005 |
| AVA Nguyen Ltd | Real estate | 2025 |
| AVA Properties (NE) Ltd | Real estate | 2019 |
| Avalon One Ltd | Arts & recreation | 2020 |
| Aveera Vaani Ltd | Real estate | 2024 |
| Avenue (North East) Limited | Financial services | 2013 |
| AVENUE2025 Ltd | Hospitality | 2025 |
| AVIR2AL Ltd | Professional & scientific | 2022 |
| Avok Publishing Ltd | Information & communication | 2022 |
| Avora Health Ltd | Wholesale & retail | 2025 |
| Avtar Kamal Properties Ltd | Real estate | 2023 |
| AW Electricals (N.E) Ltd | Construction | 2023 |
| AW Mechanical and Training Limited | Manufacturing | 2023 |
| AW MOT Services Ltd | Wholesale & retail | 2025 |
| Awescoj Ltd | Health & social care | 2022 |
| Axiaday Ltd | Professional & scientific | 2025 |
| Axis Aluminium Systems Ltd | Wholesale & retail | 2026 |
| Aydon House 96 Limited | Real estate | 1995 |
| Ayetonis Limited | Health & social care | 2024 |
| Ayhan NE Ltd | Hospitality | 2017 |
| Ayla 4 Limited | Education | 2017 |
| Aylas Retreats Ltd | Hospitality | 2021 |
| Ayngaran Retail Group Ltd | Wholesale & retail | 2026 |
| Ayomi Limited | Transport & logistics | 2026 |
| Aysr Curry Limited | Hospitality | 2024 |
| Ayton Financial Management Limited | Administrative & support | 2006 |
| Azhin Properties Ltd | Real estate | 2022 |
| Azimuth Design Limited | Professional & scientific | 2009 |
| Azriel Care Initiative CIC | Health & social care | 2024 |
| Aztec Printwear Ltd | Manufacturing | 2024 |
| Azure (AE Fond Kiss) LLP | | 2003 |
| Azuris Health Limited | Health & social care | 2018 |
| B and R Property Limited | Real estate | 2002 |
| B Appleby Property Limited | Real estate | 2026 |
| B Dodd Ltd | Manufacturing | 2026 |
| B J Cloak Medical Services Ltd | Health & social care | 2019 |
| B Line Rapid Response Ltd | Manufacturing | 2026 |
| B N MS Home Bargains Limited | Real estate | 2020 |
| B&A Capital Ltd | Real estate | 2025 |
| B&H Domestic Support Services Ltd | Households | 2021 |
| B&T Groundworks Ltd | Administrative & support | 2026 |
| B&W Consultancy Limited | Information & communication | 2026 |
| B' Active 'N' B' Fit CIC | Arts & recreation | 2005 |
| B. D. Plastics Holdings Limited | Real estate | 2013 |
| B. D. Plastics Limited | Wholesale & retail | 1998 |
| B.C.L Electrics Ltd | Construction | 2014 |
| Baaz Dhillon Limited | Real estate | 2020 |
| Baba CAN Ltd | Hospitality | 2025 |
| BABAJI21 Limited | Hospitality | 2025 |
| BABAJI5 Limited | Real estate | 2025 |
| Babak Shirin Ltd | Hospitality | 2024 |
| Baby Sensory Chester-Le-Street Ltd | Education | 2020 |
| BAC Properties NE Ltd | Real estate | 2019 |
| Back on the MAP Enterprises Limited | Real estate | 2010 |
| Back on the MAP Limited | Real estate | 2004 |
| Badger Human Resources Limited | Administrative & support | 2001 |
| Bagherland Ltd | Hospitality | 2026 |
| Bahary Pharma Ltd | Health & social care | 2024 |
| Bailey & BO Limited | Professional & scientific | 2014 |
| Bain & Hind Decorators Limited | Construction | 2012 |
| Baja Systems Ltd | Information & communication | 2019 |
| Bajwa Commercial Ltd | Real estate | 2017 |
| Bakirovi Limited | Hospitality | 2018 |