| "Richardson & Associates" Independent Financial and Mortgage Services Limited | Financial services | 2004 |
| 2A Properties Limited | Real estate | 2026 |
| 2ND Home Childcare Ltd | Health & social care | 2011 |
| 3 Reds (Property Management) Limited | Real estate | 2023 |
| 321AI Ltd | Professional & scientific | 2023 |
| 360 Total Security Planning Limited | Administrative & support | 2016 |
| 369 Plotworks Ltd | Construction | 2024 |
| 5 Circles Ltd | Professional & scientific | 2025 |
| 5 Taan Services Ltd | Transport & logistics | 2024 |
| 505 Property Maintenance Limited | Construction | 2025 |
| 6-13 Arcadia RTM Company Limited | Households | 2011 |
| 793 Spirits Limited | Manufacturing | 2021 |
| 8BALL Productions Ltd | Information & communication | 2026 |
| 91 Lodge Limited | Arts & recreation | 2025 |
| A D Joinery Limited | Construction | 2003 |
| A Dickinson Co Ltd | Construction | 2024 |
| A F Utilities Ltd | Construction | 2015 |
| A French Engineering Ltd | Professional & scientific | 2016 |
| A I Joinery and Shopfitting Ltd | Construction | 2018 |
| A N a Housing Limited | Real estate | 2024 |
| A&A Rowlands Limited | Information & communication | 2024 |
| A&G Events Ltd | Administrative & support | 2018 |
| A&S MAY Roofing Ltd | Construction | 2021 |
| A&S Products Sale Ltd | Wholesale & retail | 2026 |
| A. C. Emmerson Joinery Limited | Construction | 2002 |
| A.D.C. Halford & Company Limited | Manufacturing | 1998 |
| A.G. Security Limited | Administrative & support | 2016 |
| A.S.L Utilities Ltd | Construction | 2023 |
| A1 Elevate Roofing Ltd | Construction | 2026 |
| A1 Self Storage & More Ltd | Transport & logistics | 2021 |
| A1 Stage Ltd | Manufacturing | 2011 |
| A19 Developments Limited | Real estate | 2002 |
| AB Joinery & Building Ltd | Construction | 2018 |
| Abbott Dance Theatre Limited | Arts & recreation | 2018 |
| Abdul Bari Ltd | Wholesale & retail | 2025 |
| Acceptional Consulting Solutions Ltd | Administrative & support | 2018 |
| Accident Legal Group Limited | Professional & scientific | 2000 |
| Accountability Derbyshire Ltd | Professional & scientific | 2018 |
| Accountability South Tyneside Ltd | Professional & scientific | 2025 |
| ACL Brickworks (Birtley) Ltd | Administrative & support | 2025 |
| Active Individual Mortgage Solutions Limited | Financial services | 2020 |
| Active Mind and Body Limited | Health & social care | 2024 |
| Acupunture Plus UK Ltd | Other services | 2009 |
| AD Rusk Ltd | Other services | 2011 |
| Adam Dudley Ltd | Professional & scientific | 2024 |
| Adas Solutions Ltd | Wholesale & retail | 2018 |
| ADH Subsea Technical Services Limited | Professional & scientific | 2015 |
| Adpcom Ltd | Transport & logistics | 2024 |
| ADR Properties (NE) Ltd | Real estate | 2026 |
| Adsr Market Limited | Wholesale & retail | 2021 |
| Advanced Kitchens Ltd | Manufacturing | 2026 |
| Advocate Residential Services Limited | Health & social care | 2020 |
| AE Facilities Limited | Construction | 2017 |
| AF Installation Services Ltd | Construction | 2017 |
| AF3CA Ltd | Financial services | 2023 |
| Afri-Labs Ltd | Professional & scientific | 2024 |
| AG Anderson Building & Landscaping Ltd | Construction | 2017 |
| AH Sing Building Ltd | Construction | 2019 |
| Ahamza Ltd | Wholesale & retail | 2025 |
| Ahmh Limited | Professional & scientific | 2026 |
| Ahsan Group Ltd | Wholesale & retail | 2025 |
| AI & Network Tech Ltd | Information & communication | 2025 |
| AI Technology North Limited | Information & communication | 2026 |
| AI101.UK Ltd | Education | 2026 |
| Aioli Restaurant Limited | Hospitality | 2023 |
| Air Hound Ltd. | Professional & scientific | 2017 |
| Air Supply (Teesside) Limited | Manufacturing | 2024 |
| Airow Defence Deployment Limited | Extraterritorial | 2014 |
| AJ SCM Consultant Ltd | Professional & scientific | 2024 |
| AJF Property Solutions Ltd | Construction | 2013 |
| AJH180 Limited | Arts & recreation | 2020 |
| AJT Legal Services Ltd | Professional & scientific | 2015 |
| AK Geoservices Ltd | Professional & scientific | 2018 |
| AKK Stays Limited | Real estate | 2026 |
| AL Maini Group Ltd | Professional & scientific | 2024 |
| Al's Diner (North East) Ltd | Hospitality | 2025 |
| Alan LAM Family Dental Practice Limited | Health & social care | 2007 |
| Alanalanalan Limited | Professional & scientific | 2015 |
| ALD Hairdressing Training Academy Ltd | Other services | 2025 |
| Alex Lewis Ltd | Health & social care | 2016 |
| Alexandros NCL Limited | Other services | 2023 |
| ALL About Training Limited | Education | 2012 |
| ALL Saints Property Investments Limited | Real estate | 2015 |
| ALL Seasons Developments Ltd | Real estate | 2017 |
| ALL Seasons Leisure Limited | Manufacturing | 2019 |
| ALL Sorts Plus Ltd | Wholesale & retail | 2025 |
| ALL Stars Sport Ltd | Education | 2012 |
| ALL That IS SHE Ltd | Wholesale & retail | 2018 |
| Alone Productions Limited | Information & communication | 2020 |
| Alpha Iconic Ltd | Professional & scientific | 2025 |
| Althena Properties Limited | Real estate | 2025 |
| Alu-Tek Ltd | Construction | 2021 |
| ALW Consultancy Services Ltd | Information & communication | 2014 |
| Amaasale Ltd | Wholesale & retail | 2024 |
| Amak Hire Ltd | Administrative & support | 2023 |
| Amberstone Design Limited | Professional & scientific | 2025 |
| Ambic Limited | Manufacturing | 2001 |
| Ambr Consulting Limited | Professional & scientific | 2016 |
| AML Property Management Limited | Real estate | 2011 |
| Amp-Tech Solutions Limited | Construction | 2025 |