| Aloha Brick Ltd | Wholesale & retail | 2019 |
| Alpaca Parcel Ltd | Administrative & support | 2019 |
| Alpine Online Ltd | Professional & scientific | 2019 |
| ALRR4 Ltd | Real estate | 2018 |
| ALT Properties and Investments Ltd | Real estate | 2026 |
| Altius Images Ltd | Professional & scientific | 2018 |
| Aly's Bakery Limited | Wholesale & retail | 2024 |
| AM 365 Limited | Construction | 2014 |
| AM B2C Limited | Wholesale & retail | 2023 |
| Amaze Krhh Ltd | Hospitality | 2024 |
| Amble Roofing Ltd | Other services | 2008 |
| Amer 18 Financial Limited | Financial services | 2017 |
| Amica Limited | Professional & scientific | 1986 |
| AN Accountant Limited | Professional & scientific | 2007 |
| AND YOU Limited | Professional & scientific | 2020 |
| Andersons Monkseaton Limited | Real estate | 2025 |
| Andersson Subsea Ltd | Professional & scientific | 2026 |
| Andover Consultancy Services Limited | Real estate | 2021 |
| Andover Property Management Limited | Real estate | 2021 |
| Andrew Chambers Financial Services Limited | Financial services | 2026 |
| Andrew J Williams Ltd | Manufacturing | 2023 |
| Andrewstaylor.Com Ltd | Information & communication | 2023 |
| Angelas Whitley Bay Pet Supplies Ltd | Wholesale & retail | 2026 |
| Angie Brown Music Group Ltd | Professional & scientific | 2025 |
| Annethomas Workwear Limited | Wholesale & retail | 2007 |
| Annitsford Convenience Store Ltd | Wholesale & retail | 2022 |
| Annville Cleaning Services Limited | Other services | 2018 |
| Anotherway Works Ltd | Professional & scientific | 2025 |
| Anva Consulting Ltd | Information & communication | 2017 |
| ANY Metals NE Ltd | Wholesale & retail | 2025 |
| AP Jointing Limited | Construction | 2012 |
| AP Taylor Locums Ltd | Professional & scientific | 2019 |
| Apex Education NE Limited | Education | 2026 |
| Apex Fabrication Ltd | Manufacturing | 2018 |
| Apls Property Ltd | Real estate | 2020 |
| App Entertainment Ltd | Other services | 2014 |
| Appletree Court RTM Company Limited | Households | 2009 |
| Appliance Centre NE Ltd | Other services | 2004 |
| Aquaproof Roofing Limited | Construction | 2018 |
| Arcadia Paving and Landscaping Limited | Administrative & support | 2021 |
| Arcot Commercial Ltd | Financial services | 2018 |
| Arcturus Digital Media Limited | Information & communication | 2019 |
| Areola Academy Ltd | Education | 2025 |
| Aretai International Limited | Professional & scientific | 2024 |
| Arete Arts Community Ltd | Wholesale & retail | 2022 |
| ARK Software Solutions Limited | Information & communication | 2001 |
| Arluchi Plastering Division Ltd | Construction | 2017 |
| Armour Solutions (NE) Limited | Construction | 2017 |
| Armstrong Carpentry Limited | Construction | 2015 |
| Aroos Beirut NE Ltd | Hospitality | 2017 |
| ARP Design & Build Limited | Construction | 2020 |
| Artichoke Heaton Limited | Wholesale & retail | 2025 |
| Artisttree C.I.C. | Information & communication | 2025 |
| Arty JOE Limited | Wholesale & retail | 2026 |
| AS Draper Scaffolding Ltd | Construction | 2025 |
| As-New Auto Recyclers Ltd | Wholesale & retail | 2008 |
| ASF Property Developments Ltd | Real estate | 2021 |
| ASK MRS Watson Limited | Extraterritorial | 2015 |
| Aston Wind Services Ltd | Education | 2023 |
| Atkinson Property Enhancements Ltd | Real estate | 2022 |
| Atkinson Technical Ltd | Information & communication | 2025 |
| Atre Ltd | Real estate | 2022 |
| Atticus Lucas Ltd | Real estate | 2023 |
| Autofix (North East) Limited | Wholesale & retail | 2007 |
| Autostyle Breakers Limited | Wholesale & retail | 2009 |
| Autostyle Garage Services Limited | Wholesale & retail | 2009 |
| Avalon Property Sourcing Ltd | Real estate | 2020 |
| AW Property Developments (NE) Ltd | Construction | 2018 |
| AWA Accountancy Limited | Professional & scientific | 2026 |
| Awesome North Ltd | Wholesale & retail | 2024 |
| Axwell Homes Limited | Real estate | 2025 |
| Ayda Investments Ltd | Real estate | 2023 |
| Azendo Beauty Lounge Ltd | Other services | 2019 |
| B & C Plant Ltd | Professional & scientific | 2018 |
| B Arthur & SON Limited | Construction | 2008 |
| B M Commercial Holdings Limited | Real estate | 2022 |
| B Young Consulting Ltd | Financial services | 2021 |
| B. Herridge Contracts Limited | Professional & scientific | 2015 |
| B.A. Hardy Electrical Ltd | Professional & scientific | 2025 |
| B.E.P. PUB Company Limited | Hospitality | 2019 |
| Baba Yaga's House Ltd | Hospitality | 2021 |
| Baby BUN Music Limited | Information & communication | 1971 |
| Baby Lights Ltd | Wholesale & retail | 2025 |
| Bab’S Plaice Limited | Other services | 2017 |
| Backslashbackslashbackslash Limited | Information & communication | 2011 |
| Baines Offshore Ltd | Transport & logistics | 2025 |
| Ballantyne Properties Group Limited | Real estate | 2022 |
| Bambury House Limited | Real estate | 2014 |
| Banbury Print Lamination Services Ltd | Professional & scientific | 2007 |
| Bar 79 Limited | Hospitality | 2022 |
| Bardymala Limited | Construction | 2024 |
| Barjac Limited | Professional & scientific | 2013 |
| Barrass Residential Ltd | Real estate | 2024 |
| Base Psychology Ltd | Health & social care | 2024 |
| Baskrate Ltd | Professional & scientific | 2026 |
| BAT Property Developments Limited | Construction | 2005 |
| Bathrooms and Kitchens Whitley Bay Ltd | Construction | 2020 |
| Bay Beauty Academy Ltd | Education | 2015 |
| Bay Financial Ltd | Administrative & support | 2025 |
| Bay Food Group Limited | Hospitality | 2026 |