| Aspect Health Media Ltd | Administrative & support | 2016 |
| Aspire NE Properties Ltd | Construction | 2025 |
| Aspire Wealth Limited | Financial services | 2014 |
| Athena Creations Limited | Extraterritorial | 2020 |
| Athenalink Limited | Real estate | 1993 |
| ATM Security Ltd | Manufacturing | 2013 |
| Atsfinancialservices Ltd | Financial services | 2023 |
| AUK (RPE) Limited | Professional & scientific | 2001 |
| AUK Distribution Ltd | Manufacturing | 2009 |
| AUR Engineering Ltd | Construction | 2023 |
| Aura Events NE Limited | Other services | 2017 |
| Aurora Care Group Ltd | Professional & scientific | 2008 |
| Aurora Home Care Ltd | Health & social care | 2011 |
| Automatic Retailing (Vending) Limited | Extraterritorial | 2017 |
| Automatic Retailing Coffee Services Limited | Extraterritorial | 2011 |
| Avertis Group Limited | Information & communication | 2025 |
| Avery Dennison Materials U.K. Limited | Manufacturing | 1969 |
| Avery Dennison UK II Limited | Wholesale & retail | 2003 |
| AW Publications Ltd | Information & communication | 2013 |
| AWS Accountancy Limited | Professional & scientific | 2006 |
| Aysee Ltd | Hospitality | 2023 |
| Azure College Ltd | Education | 2025 |
| Azure Property Management Services Ltd | Real estate | 2003 |
| B Village Ltd | Real estate | 2017 |
| B.& B. Attachments Limited | Manufacturing | 1980 |
| B7 NE Ltd | Manufacturing | 2024 |
| Baban Barber Shop (Cramlington) Ltd | Other services | 2026 |
| Baban Barber Shop Ltd | Other services | 2018 |
| Baghead Ltd | Hospitality | 2026 |
| Bain Medical Management Consultant Ltd. | Professional & scientific | 2009 |
| Bainbridge Search Ltd | Professional & scientific | 2024 |
| Baird Group NE Ltd | Construction | 2021 |
| Baird Property Group Ltd | Real estate | 2014 |
| Balmoral Joinery Limited | Construction | 2003 |
| Balmoral P & M Limited | Administrative & support | 2011 |
| Batch & BOW Properties Ltd | Real estate | 2024 |
| Bats and Trees Ltd | Professional & scientific | 2019 |
| Bay Investments (NE) Ltd | Real estate | 2018 |
| Beacon Local Store Limited | Wholesale & retail | 2014 |
| Beanbag Bazaar Limited | Extraterritorial | 2014 |
| Beaufort Estates & Investments Ltd | Hospitality | 2026 |
| Bebside Motors Limited | Real estate | 1976 |
| Belian Limited | Wholesale & retail | 2023 |
| BELOW280 Limited | Professional & scientific | 2026 |
| Belta’S Ltd | Hospitality | 2025 |
| Benchmark 365 Ltd | Transport & logistics | 2020 |
| Benridge Riding Centre Limited | Arts & recreation | 2019 |
| Berg Tech Services Ltd | Information & communication | 2025 |
| Bergot Holdings Limited | Professional & scientific | 2021 |
| Bermal Limited | Professional & scientific | 2017 |
| Bewick Gardening Services (Newcastle) Limited | Administrative & support | 1976 |
| Bgrp Holdings Limited | Financial services | 2021 |
| Bgrp Limited | Manufacturing | 2005 |
| BIOQ8 Ltd | Professional & scientific | 2015 |
| Blackpool Property and Leisure Ltd | Real estate | 2022 |
| Blades Electrical Contractors Limited | Construction | 2020 |
| Blagdon Projects UK Ltd | Administrative & support | 2023 |
| BLI Pizza Limited | Hospitality | 2026 |
| Bloc Electrical Ltd | Wholesale & retail | 2014 |
| Blucore Property Care Limited | Construction | 2014 |
| Blue Giraffe Consultancy Ltd | Professional & scientific | 2022 |
| Blyth Town Football Club Ltd | Arts & recreation | 2021 |
| BM Renewables Limited | Professional & scientific | 2024 |
| BML PN Limited | Administrative & support | 2017 |
| Boiler Care NE Ltd | Construction | 2025 |
| Bolam Group Limited | Administrative & support | 2016 |
| BON Construction Ltd | Professional & scientific | 2015 |
| Bowman Contracts North East Ltd | Construction | 2025 |
| Bowman Surveying and Design Ltd | Construction | 2013 |
| Bracken Property Investments Limited | Construction | 2025 |
| Braden UK Limited | Professional & scientific | 2021 |
| Brantwood Recruitment Ltd | Administrative & support | 2019 |
| Brennan Drylining Ltd | Construction | 2013 |
| Brian's Guitar Studio Ltd | Education | 2025 |
| Bright Blue Training and Advisory Ltd | Education | 2008 |
| Briham Limited | Extraterritorial | 1986 |
| Britannia-Health Ltd | Health & social care | 2025 |
| Brockwell Spice Ltd | Hospitality | 2018 |
| Brockwell Survey & Design Ltd | Information & communication | 2026 |
| Broke & Knackered Films Ltd | Information & communication | 2026 |
| Browells Services Limited | Professional & scientific | 2010 |
| Brown's Recruitment and Training Consultancy Ltd | Administrative & support | 2009 |
| Browns Bedrooms & Kitchens Ltd | Manufacturing | 1999 |
| Bryan Crisp & SON Specialist Services Limited | Construction | 2013 |
| Burgess IT Limited | Information & communication | 2011 |
| Burradon Autocare Ltd | Wholesale & retail | 2025 |
| Burtonhouse Ltd | Hospitality | 2026 |
| Business Consultants (Northumbria) Limited | Other services | 1994 |
| Business Transformation Associates Ltd. | Professional & scientific | 2013 |
| Bute Aerotech Ltd | Professional & scientific | 2018 |
| Buzz Smoothies & Shakes Limited | Wholesale & retail | 2013 |
| Bxhco Limited | Information & communication | 2022 |
| Bytemunch Studios Limited | Information & communication | 2025 |
| C & a Properties (North East) Ltd | Real estate | 2020 |
| C Patrick Mgmt Ltd | Other services | 2020 |
| C Patrick Properties Ltd | Real estate | 2023 |
| C R S Engineering Limited | Manufacturing | 2003 |
| C.R.T. Packaging (U.K.) Limited | Wholesale & retail | 1996 |
| CAD 21 (North West) Limited | Professional & scientific | 2016 |
| CAD 21 (Yorkshire) Limited | Professional & scientific | 2010 |