| Andy Laurie Construction Consultancy Limited | Professional & scientific | 2011 |
| Anela Wedding Wear Ltd | Wholesale & retail | 2025 |
| Angelas Beauty Ltd | Other services | 2018 |
| Angelas Hair Ltd | Other services | 2018 |
| Angeltek Cleaning & Building Services Ltd | Administrative & support | 2012 |
| Anglitemp Limited | Manufacturing | 1979 |
| Anlt Sports Holdings Ltd | Education | 2022 |
| Another Cheap Thrill Ltd | Arts & recreation | 2025 |
| Another Loop Ltd | Manufacturing | 2025 |
| Antfrogboy Limited | Professional & scientific | 2020 |
| Anthony Lo-Giudice Dance Theatre Limited | Arts & recreation | 2026 |
| AO Waste Management Ltd | Water & waste | 2025 |
| AP Bulmer Services Limited | Health & social care | 2014 |
| AP Home Solutions Ltd | Construction | 2020 |
| Aperture Ales Ltd | Hospitality | 2025 |
| Apex Pro Fitness Limited | Arts & recreation | 2018 |
| Appyhive Ltd. | Information & communication | 2019 |
| Apron Safety Limited | Public administration | 2022 |
| APS Detailing Ltd | Wholesale & retail | 2022 |
| APS Films Ltd | Wholesale & retail | 2024 |
| Aqua Leisure Management Ltd | Real estate | 2016 |
| Aquanorth Vocational Training Limited | Education | 1996 |
| AR & K Nabi Ltd | Real estate | 2016 |
| Arbor Seven Limited | Hospitality | 2025 |
| ARC Force One Welding Ltd | Construction | 2019 |
| Arca Property Limited | Real estate | 2024 |
| Arconia Engineering Ltd | Manufacturing | 2008 |
| Arcus Spmu Ltd | Other services | 2024 |
| ARE YOU Affiliated Ltd | Arts & recreation | 2024 |
| Argco Limited | Professional & scientific | 2016 |
| Arh.Dickas Ltd | Hospitality | 2025 |
| ARI Sushi Ltd | Hospitality | 2023 |
| ARK Search Group Limited | Administrative & support | 2026 |
| Arles Ltd | Manufacturing | 2025 |
| Armstrong and Partners Ltd | Administrative & support | 2013 |
| Armstrongs Services Limited | Professional & scientific | 2024 |
| Armtec Engineering Ltd | Manufacturing | 2016 |
| Arne Offshore Solutions Ltd | Professional & scientific | 2025 |
| Artetech Limited | Professional & scientific | 2020 |
| Artichoke Tynemouth Ltd | Wholesale & retail | 2019 |
| AS Store NE Ltd | Wholesale & retail | 2019 |
| Asco Wind Ltd | Professional & scientific | 2023 |
| Ascott GAS Services Limited | Construction | 2015 |
| Ashford Grove Management Limited | Real estate | 2017 |
| Ashington Wedding Chapel Ltd | Hospitality | 2025 |
| Ashleigh Building Services Ltd | Construction | 2018 |
| Ashwood Accountancy Services Ltd | Professional & scientific | 2010 |
| Ashworth Marketing Limited | Information & communication | 2010 |
| Aspect Safety Solutions Ltd | Administrative & support | 2018 |
| Assurance Intelligence Limited | Professional & scientific | 2025 |
| Assured Innovations Limited | Information & communication | 2011 |
| Astley Bay Properties Ltd | Real estate | 2012 |
| Aston Beaumont Ltd | Real estate | 2022 |
| Astral Control Services Limited | Construction | 2002 |
| Astryan NE Ltd | Construction | 2019 |
| Atelerix Limited | Professional & scientific | 2017 |
| ATN Holdings & Commodities Ltd | Financial services | 2023 |
| Atolla Electrical Ltd | Construction | 2026 |
| Atomic Precision Engineering Ltd | Manufacturing | 2021 |
| Atomic Workholding Ltd | Manufacturing | 2023 |
| Attic North East Limited | Construction | 2025 |
| Attic Protect Ltd | Construction | 2025 |
| Aubergine Hairdressing Ltd | Other services | 2007 |
| Audiowalks Ltd | Information & communication | 2026 |
| Augmentum Digital Ltd | Professional & scientific | 2025 |
| Austin Burke Subsea Ltd | Professional & scientific | 2022 |
| Autocare Services (NS) Limited | Wholesale & retail | 2008 |
| Automatic Retailing (Northern) Limited | Wholesale & retail | 1988 |
| Autonim Ltd | Information & communication | 2021 |
| Autotool Expert Limited | Wholesale & retail | 2015 |
| Autreach | Information & communication | 2012 |
| AVM Properties Ltd | Real estate | 2016 |
| Avocado and Chickpeas Ltd | Hospitality | 2020 |
| Aylwin Welding & Fabrications Ltd | Construction | 2026 |
| Azure Therapy and Wellness Centre Ltd | Health & social care | 2024 |
| B Walker Catering Limited | Other services | 2024 |
| B&Fnm Investments Ltd | Financial services | 2026 |
| B&M Spa Products Ltd | Other services | 2024 |
| B.I.C. PLC | Administrative & support | 1988 |
| Baba’S Loft Ltd | Hospitality | 2024 |
| Baby Thrive Limited | Health & social care | 2022 |
| Babydoll Beauty Ltd | Other services | 2020 |
| Babysense Ltd. | Health & social care | 2018 |
| Baca Cleaning Ltd | Administrative & support | 2012 |
| Bach Mill Consultants Ltd | Manufacturing | 2024 |
| BAG Sales & Management Consultancy Limited | Professional & scientific | 2019 |
| Bailey & Harlow Limited | Construction | 2018 |
| Bait Box Catering Ltd | Hospitality | 2025 |
| Ball Real Estate Ltd | Real estate | 2022 |
| Balls UN Limited | Hospitality | 2024 |
| Balmer Property Ltd | Real estate | 2022 |
| Balmoral PUB Co Limited | Hospitality | 2019 |
| Banara Trading Ltd | Wholesale & retail | 2025 |
| Banzai Motors Limited | Wholesale & retail | 2003 |
| Bar Dona Ltd | Hospitality | 2020 |
| Barca Tynemouth Ltd | Hospitality | 2017 |
| Bargain Point Ltd | Wholesale & retail | 2025 |
| Baristocracy Coffee Limited | Manufacturing | 2017 |
| Barrehaus Ltd | Arts & recreation | 2018 |
| Barrys Fruit & VEG Ltd | Wholesale & retail | 2023 |