| 103 Ifield Road 2010 Limited | Households | 2010 |
| 1031 Heating and Insulation Ltd | Construction | 2025 |
| 1031 Solutions Limited | Transport & logistics | 2022 |
| 162-164 Park Avenue Management Company Limited | Real estate | 2008 |
| 18 Leonard Street Limited | Households | 2018 |
| 18 Pins Ltd | Arts & recreation | 2025 |
| 183 Lounge Ltd | Hospitality | 2025 |
| 2 Granville Road RTM Company Limited | Households | 2015 |
| 21 North Parade Management Company Limited | Real estate | 2008 |
| 32 Delaval Road Freehold Management Ltd | Households | 2025 |
| 35 Percy Park Management Company Limited | Households | 1995 |
| 37 Degree Solutions Ltd | Construction | 2020 |
| 38 Madeira Road Flats Management Co. Ltd | Households | 2013 |
| 4 Osborne Terrace RTM Company Limited | Real estate | 2015 |
| 46 Front Street Management Company Limited | Households | 2017 |
| 5 Element Production Limited | Information & communication | 2013 |
| 5 Rockcliffe Gardens Management Company Limited | Real estate | 1999 |
| 50/52 Marine Avenue Management Company Limited | Households | 1998 |
| 55 Marine Avenue Management Company Limited | Real estate | 2010 |
| 6 Mason Avenue Limited | Households | 1997 |
| 60 Park Avenue Management Company Limited | Households | 2005 |
| 65 Marine Avenue Management Co Limited | Real estate | 2020 |
| 65HOURS Limited | Information & communication | 2011 |
| 92 Beats Productions Ltd | Arts & recreation | 2025 |
| A & F Getaways Limited | Hospitality | 2023 |
| A & K Blinds Limited | Wholesale & retail | 2003 |
| A Fulthorpe Ltd | Construction | 2006 |
| A G M Joinery Services Limited | Construction | 2011 |
| A J Walton Surveying Limited | Professional & scientific | 2015 |
| A M S Electrical (North East) Limited | Construction | 2008 |
| A N Metals Limited | Water & waste | 2019 |
| A T F Retail Limited | Real estate | 2014 |
| A T.V. Aerial & Satellite Co Ltd | Information & communication | 2006 |
| A&A Eyecare Ltd | Wholesale & retail | 2024 |
| A&J Property Developments Limited | Real estate | 2026 |
| A.C.E Interventions Ltd | Health & social care | 2020 |
| A.J.Nazar & Sons Limited | Real estate | 2023 |
| A.K Fitness Ltd. | Arts & recreation | 2015 |
| A1 Barber (Seaton Delaval) Ltd | Other services | 2024 |
| A1 Forklift Truck Training Limited | Education | 2012 |
| A2 Creative Limited | Professional & scientific | 2004 |
| AA Flat Roofing & Property Maintenance Ltd | Construction | 2026 |
| Aaaj Properties Limited | Real estate | 2022 |
| AAE Craddock Limited | Other services | 2023 |
| AB Northern Accounting Limited | Professional & scientific | 2022 |
| AB Northern Living Limited | Real estate | 2019 |
| Ab-Solve Limited | Professional & scientific | 2012 |
| ABLE2FLY Limited | Information & communication | 2012 |
| Absolute Developments and Renovations (North East) Limited | Construction | 2023 |
| Absolute Developments and Renovations Ltd | Construction | 2009 |
| AC Garden Build Solutions Limited | Construction | 2023 |
| Adar Catering Limited | Hospitality | 2025 |
| Adderstone Park Management Company Limited | Households | 1971 |
| Adeptio Solutions Limited | Administrative & support | 2013 |
| Admiral Imports UK Ltd | Wholesale & retail | 2026 |
| Adsnet Limited | Construction | 2020 |
| Advanced Control Systems Limited | Information & communication | 1985 |
| Advanced Vision @ Tynemouth Limited | Real estate | 2011 |
| Advanced Vision Limited | Real estate | 2003 |
| Advintage Limited | Administrative & support | 2010 |
| Aerspace Limited | Real estate | 2021 |
| AF Geologic Limited | Professional & scientific | 2012 |
| Afcomm Ltd | Information & communication | 2026 |
| Affiliate Family Limited | Information & communication | 2003 |
| Affirming Catholicism | Education | 2007 |
| AGC Commercial Holdings Limited | Real estate | 2025 |
| AGC Residential Limited | Real estate | 2023 |
| AH Ecology Limited | Professional & scientific | 2025 |
| AHD Properties Limited | Real estate | 2009 |
| Ahmed's TME Surgicals Ltd | Health & social care | 2026 |
| AI Soria Ltd | Information & communication | 2025 |
| Ainsley Motor Werks Ltd | Professional & scientific | 2024 |
| Air Tight Edits Ltd | Information & communication | 2017 |
| Airband (NE) Ltd | Administrative & support | 2005 |
| Ajax Tech Solutions Ltd | Construction | 2022 |
| AJK Properties Limited | Real estate | 2000 |
| AJS Investment Properties Limited | Real estate | 2023 |
| AK Castlegate Ltd | Wholesale & retail | 2025 |
| Akenside Terrace Management Limited | Households | 2004 |
| Akmmc Ltd | Manufacturing | 2026 |
| Akwaaba Travel Limited | Administrative & support | 2022 |
| Al-Mogni Ltd | Hospitality | 2025 |
| Alan Christie Limited | Manufacturing | 2014 |
| Alan Dunton Pipelines Limited | Professional & scientific | 2007 |
| Alan Holmes Building Surveying Services Limited | Professional & scientific | 2002 |
| Alanichem Limited | Wholesale & retail | 2018 |
| Albany Care Homes Limited | Health & social care | 2006 |
| Albert Gurney Associates Limited | Professional & scientific | 2014 |
| ALC Hospitality Limited | Hospitality | 2024 |
| Alcove Cabinet Company Limited | Manufacturing | 2021 |
| Alderson Fundraising Ltd | Information & communication | 2021 |
| Alex Gales Limited | Manufacturing | 2022 |
| Alexander & Co Estate Agents Limited | Real estate | 2010 |
| Alexzel Health Care Limeted Ltd | Health & social care | 2022 |
| ALF Group Ltd | Real estate | 2026 |
| Alfatech N.E. Ltd | Wholesale & retail | 2023 |
| ALL Heat North East Ltd | Construction | 2012 |
| Allforone Roofing Ltd | Construction | 2025 |
| Alnwick Healthcare Ltd | Extraterritorial | 2023 |
| Alnwick House Development Limited | Households | 2005 |