| Ahcs Prop Holdings Ltd | Real estate | 2022 |
| Ahead Holdings Ltd | Financial services | 2024 |
| AHG Advisory Ltd | Administrative & support | 2020 |
| AHJ1984 Limited | Professional & scientific | 2022 |
| AHM Properties (Newcastle) Ltd | Real estate | 2021 |
| Ahmad Consultants Limited | Information & communication | 2008 |
| Ahmad Investments Ltd | Real estate | 2014 |
| Ahmad Vision Limited | Health & social care | 2017 |
| Ahmadillo Healthcare Ltd | Health & social care | 2026 |
| Ahmadillo Limited | Real estate | 2025 |
| Ahman Ltd | Hospitality | 2026 |
| Ahmed Abdullah Limited | Health & social care | 2008 |
| Ahmed Properties Newcastle Limited | Real estate | 2021 |
| AHZ Tech Ltd | Information & communication | 2025 |
| AI Fiori Ltd | Hospitality | 2026 |
| AI Health Solutions Ltd | Manufacturing | 2026 |
| AI Newcastle Ltd | Hospitality | 2023 |
| AI Sky AUS Finance Limited | Financial services | 2019 |
| AI Sky CDN Finance Limited | Financial services | 2020 |
| AI Sky NZ Finance Limited | Financial services | 2019 |
| AI Sky UK Bidco Limited | Financial services | 2019 |
| AI Sky UK Holdco Limited | Financial services | 2019 |
| AI5 Limited | Information & communication | 1998 |
| Aiatella Ltd | Information & communication | 2022 |
| Aiba Consultancy Ltd | Professional & scientific | 2017 |
| Aiba Home Solutions Limited | Construction | 2019 |
| Aibody Limited | Professional & scientific | 2018 |
| AID Automotive Ltd | Wholesale & retail | 2013 |
| AIG (AL) Ltd | Real estate | 2023 |
| AIG (Halo) Dunstable Ltd | Real estate | 2026 |
| AIG (Halo) Ltd | Real estate | 2023 |
| AIG (KH) Ltd | Real estate | 2023 |
| AIG (SLB) Ltd | Real estate | 2023 |
| AIG Health Limited | Professional & scientific | 2026 |
| AIG Property Holdings Ltd | Real estate | 2023 |
| Aignite Automation Limited | Information & communication | 2026 |
| AII Property Limited | Real estate | 2024 |
| Aikai Ltd | Real estate | 2024 |
| Ailantus Hotels Limited | Hospitality | 2003 |
| Ailments. Limited | Wholesale & retail | 2024 |
| AIM Studio Ltd | Arts & recreation | 2023 |
| Aimgo Limited | Other services | 1989 |
| Ainoa Brands Ltd | Professional & scientific | 2022 |
| Ainsworth Spark Associates LLP | | 2021 |
| Aion Health Care Ltd | Health & social care | 2024 |
| Aiquin Nails Limited | Other services | 2019 |
| Air Conditioning & Refrigeration Services (Newcastle) Limited | Energy | 1979 |
| Air-Aid Limited | Administrative & support | 2026 |
| Airbridge Global Limited | Information & communication | 2023 |
| Aircards Ltd | Information & communication | 2020 |
| Airconnorth Ltd | Construction | 2024 |
| Airesta Properties Ltd | Real estate | 2025 |
| Airfotos Limited | Professional & scientific | 1989 |
| Airleon Limited | Wholesale & retail | 2023 |
| Airport Taxis 24/7 Limited | Transport & logistics | 2019 |
| Airways Wind Limited | Manufacturing | 2026 |
| Airworthiness Limited | Professional & scientific | 2026 |
| Airworx Ltd | Professional & scientific | 2015 |
| Aisha Imran Ltd | Hospitality | 2025 |
| Aisha International Trade and Development Ltd | Wholesale & retail | 2025 |
| AIT UK Acquisition Company Limited | Financial services | 2018 |
| AIT UK Holdings Limited | Transport & logistics | 2002 |
| AIT Worldwide Logistics (UK) Limited | Transport & logistics | 1984 |
| Aitchson Holdings Limited | Financial services | 2026 |
| Aivue Ltd | Information & communication | 2026 |
| AIW Limited | Information & communication | 2024 |
| Aiylas Inventory Ltd | Wholesale & retail | 2023 |
| AJ Access Solutions Ltd | Administrative & support | 2016 |
| AJ Convenience Stores (NE) Limited | Wholesale & retail | 2021 |
| AJ Electrical Services (NE) Limited | Construction | 2021 |
| AJ Logistic Consultants Ltd. | Transport & logistics | 2017 |
| AJ Property Estates Ltd | Real estate | 2025 |
| AJ Quantity Surveying Ltd | Professional & scientific | 2023 |
| AJ Shaw Global Ltd | Manufacturing | 2024 |
| Aj's Attic Ltd | Wholesale & retail | 2022 |
| AJA FAM Investments Limited | Financial services | 2018 |
| Ajay Management Services Limited | Administrative & support | 2023 |
| Ajayi’S Enterprise Ltd | Administrative & support | 2025 |
| AJB Environmental Ltd | Wholesale & retail | 1991 |
| AJC Car Sales Ltd | Wholesale & retail | 2019 |
| AJC Logistics NE Limited | Transport & logistics | 2023 |
| AJD Group Limited | Construction | 2016 |
| AJH Autos NCL Ltd | Wholesale & retail | 2025 |
| AJH MED Limited | Health & social care | 2025 |
| AJJ Trade Pro Ltd | Financial services | 2025 |
| Ajlp Limited | Wholesale & retail | 2014 |
| Ajoho Investments Limited | Real estate | 2024 |
| AJP Recruitment Limited | Administrative & support | 2013 |
| AJR Property Group Ltd | Real estate | 2021 |
| AJS Jewellery Limited | Manufacturing | 2026 |
| AJT Northern Ltd | Financial services | 2026 |
| AJU (North East) Limited | Construction | 2021 |
| AK & Brothers Limited | Construction | 2024 |
| AK Aesthetics Services Ltd | Other services | 2024 |
| AK Autos and Tyres Ltd | Wholesale & retail | 2016 |
| AK Cramlington Kitchen Ltd | Hospitality | 2024 |
| AK Creative Consultancy Limited | Information & communication | 2019 |
| AK Gardening Ltd | Administrative & support | 2023 |
| AK Gill Ltd | Construction | 2025 |
| AK Lantsbery Ltd | Health & social care | 2023 |