| Audiverse CIC | Manufacturing | 2025 |
| Augmented Media Limited | Professional & scientific | 2024 |
| Augmentum Group Ltd | Information & communication | 2024 |
| August Medical Services Limited | Health & social care | 2012 |
| Augusta Park (Dinnington) Management Company Limited | Real estate | 2018 |
| AUM Capital Limited | Real estate | 2025 |
| Aura Cloud Services Limited | Hospitality | 2025 |
| Aura Escapes Ltd | Real estate | 2025 |
| Aura Newcastle Limited | Professional & scientific | 2006 |
| Aura Property North East Ltd | Real estate | 2025 |
| Aural Architecture Ltd | Professional & scientific | 2015 |
| Aurea Homes Limited | Wholesale & retail | 2026 |
| Aurelash Ltd | Other services | 2026 |
| Aurelia Business Services Ltd | Professional & scientific | 2020 |
| Aurelia Technology Consulting Limited | Information & communication | 2023 |
| Aureus Assets Ltd | Other services | 2026 |
| Aurochs Fitness Ltd | Extraterritorial | 2020 |
| Aurora Art Colours Ltd | Manufacturing | 2021 |
| Aurora Nights Ltd | Wholesale & retail | 2019 |
| Aurorium Holdings UK Limited | Financial services | 2003 |
| Aurorium UK Limited | Manufacturing | 1993 |
| Aurum Imperium Gold Supply Limited | Manufacturing | 2024 |
| Aurum North Limited | Information & communication | 2021 |
| Austin Consulting Limited | Professional & scientific | 2025 |
| Austin Futers Limited | Professional & scientific | 2007 |
| Austin Marshall Design Limited | Information & communication | 2014 |
| Austin Properties North East Ltd | Real estate | 2022 |
| Austopedia Limited | Real estate | 2024 |
| Austrin Gearbox Specialist Ltd | Wholesale & retail | 2012 |
| Autec GEO Limited | Administrative & support | 2007 |
| Authentic Flavours Ltd | Hospitality | 2016 |
| Authentic Indian Food Ltd | Hospitality | 2023 |
| Authentic Shilajit Ltd | Health & social care | 2023 |
| Auto Heating (Newcastle) Limited | | 1969 |
| Auto Image Ltd | Wholesale & retail | 2020 |
| Auto Inspections UK Limited | Administrative & support | 2007 |
| Auto Key Centre Ltd | Administrative & support | 2015 |
| Auto Repair Centre (Newcastle) Limited | Wholesale & retail | 2007 |
| Auto-Hero Limited | Information & communication | 2024 |
| Autobest MD Ltd | Transport & logistics | 2021 |
| Autobitz Newcastle Limited | Wholesale & retail | 2023 |
| Autoclock Systems Limited | Other services | 1982 |
| Autokleen Detailing Ltd | Administrative & support | 2024 |
| Autolink Garage Limited | Wholesale & retail | 2022 |
| Automate My Gates Ltd | Manufacturing | 2019 |
| Automated Accommodation Ltd | Hospitality | 2021 |
| Automation 4 Services Ltd | Information & communication | 2026 |
| Automotive Cleaners Limited | Other services | 2001 |
| Automotive Group (Newcastle Upon Tyne) Limited | Manufacturing | 1991 |
| Automotive Precision Experts Ltd | Wholesale & retail | 2025 |
| Autostop Limited | Wholesale & retail | 2021 |
| Autovettura Ltd | Wholesale & retail | 2020 |
| Autovolts Electric Ltd | Wholesale & retail | 2025 |
| Autumnhill One Limited | Real estate | 2021 |
| Autumnhill Properties Ltd | Real estate | 2020 |
| Autumnhill Two Limited | Financial services | 2022 |
| AV Capital Estates Ltd | Real estate | 2026 |
| AV Leisure (NE) Limited | Administrative & support | 2026 |
| AV Specialist Consulting Limited | Professional & scientific | 2017 |
| Ava-Cd Ltd | Professional & scientific | 2020 |
| Ava-Educational Technologies Ltd | Professional & scientific | 2025 |
| Avant Garde (Baslow) Limited | Construction | 2010 |
| Avant Garde Concepts Limited | Arts & recreation | 2019 |
| Avant Miller Consulting Ltd | Professional & scientific | 2020 |
| Avanti Jesmond Ltd | Administrative & support | 2022 |
| AVD Solutions Limited | Information & communication | 2021 |
| Avean Boiler Parts Ltd | Wholesale & retail | 2026 |
| Aven Properties Ltd | Real estate | 2018 |
| Avendus Capital (UK) Private Limited | Financial services | 2008 |
| Avendus Capital Asset Management (UK) Limited | Financial services | 2017 |
| Avenue 1968 Limited | Extraterritorial | 2013 |
| Avenue Development Management Limited | Real estate | 2019 |
| Avenzora Limited | Wholesale & retail | 2025 |
| Averchem Services LP | | 2017 |
| Averley Associates Limited | Health & social care | 2023 |
| Averley Investments Limited | Financial services | 2023 |
| Avia Watches Limited | Manufacturing | 2023 |
| Avian Trade Limited | Wholesale & retail | 2026 |
| Avianabijoux Limited | Wholesale & retail | 2023 |
| Aviance UK Limited | Transport & logistics | 1971 |
| Avipro Spares Ltd | Wholesale & retail | 2024 |
| Avis Accountancy Ltd | Professional & scientific | 2015 |
| AVM (Newcastle) Limited | Transport & logistics | 2014 |
| AVM Residential Ltd | Real estate | 2021 |
| Avonmouth Industrial Estates (UK) Ltd | Construction | 2020 |
| Avonmouth Industrial Estates Holdings Ltd | Real estate | 2025 |
| Avvi Ltd | Information & communication | 2023 |
| AW HR Services Ltd | Administrative & support | 2026 |
| Awais&N Ltd | Hospitality | 2026 |
| Awan Properties Limited | Real estate | 2001 |
| Awarding Body of International Occupational Safety & Health Limited | Education | 2014 |
| Aware Plus Limited | Professional & scientific | 2008 |
| Awareness AI Ltd | Information & communication | 2025 |
| Aweslege Ltd | Education | 2023 |
| Awesome Barbers Ltd | Other services | 2019 |
| Awesome Deals Ltd | Wholesale & retail | 2021 |
| Awesome Ventures Ltd | Hospitality | 2023 |
| AWF Advisory Ltd | Professional & scientific | 2021 |
| Awilli Contracting UK Ltd | Administrative & support | 2026 |
| Awlr Properties Limited | Real estate | 2018 |