| Airaa UK Limited | Real estate | 2019 |
| Airafitness Limited | Wholesale & retail | 2025 |
| Airavara Limited | Wholesale & retail | 2025 |
| Airborne Financial Services Limited | Financial services | 2011 |
| Airborne Mortgage Solutions Ltd | Financial services | 2018 |
| Aircon Mechanical Services Limited | Construction | 1999 |
| Aircon Sheet Metal Limited | Manufacturing | 2001 |
| Aircraft Records and More Ltd | Professional & scientific | 2017 |
| Aircraft Records FTL Ltd | Professional & scientific | 2026 |
| Aircrete Limited | Other services | 1987 |
| Aircrete Products Association Ltd | Other services | 1981 |
| Airemploy Ltd | Information & communication | 2021 |
| Airfield Farm Developments Limited | Professional & scientific | 2013 |
| Airgid Beithe Limited | Other services | 2023 |
| Airhorse Limited | Real estate | 2017 |
| Airiz Ltd | Information & communication | 2026 |
| Airlime Ltd | Information & communication | 2023 |
| Airlink Taxis Limited | Transport & logistics | 2020 |
| Airport Direct Leicester Limited | Extraterritorial | 2009 |
| Airsat Data Ltd | Information & communication | 2023 |
| Airside Parking Limited | Transport & logistics | 2016 |
| Airsoft Defence Ltd | Public administration | 2026 |
| Airsoft Warrior Ltd | Arts & recreation | 2022 |
| Airsoft Wholesale Supplies Ltd | Wholesale & retail | 2019 |
| Airtang Ltd | Other services | 2025 |
| Airtang Partners Ltd | Other services | 2025 |
| Airtech Renewables Ltd | Construction | 2025 |
| Airtechnology Pension Trustees Limited | Financial services | 2000 |
| Airteq Limited | Professional & scientific | 2013 |
| AIS Consultants Ltd | Education | 2025 |
| Aisata Medical Consultancy Ltd | Health & social care | 2011 |
| Aisha Arshad Associates Limited | Other services | 2009 |
| Aisha Fashion and Cosmetics Ltd | Wholesale & retail | 2025 |
| Aisha Foods Ltd | Manufacturing | 2014 |
| Aisha Group Limited | Wholesale & retail | 2020 |
| Aisha Waraich Ltd | Health & social care | 2025 |
| Aishah OPT Ltd | Health & social care | 2021 |
| Aishahh Limited | Wholesale & retail | 2020 |
| Aishaz (Leic) Ltd | Wholesale & retail | 2022 |
| Aishneet Ltd | Wholesale & retail | 2024 |
| Aishnika Group Limited | Households | 2015 |
| Aispire Analytics Limited | Professional & scientific | 2025 |
| AIT Medical Services Ltd | Administrative & support | 2016 |
| AIT Properties Ltd | Real estate | 2018 |
| Aitbop Limited | Other services | 2025 |
| Aitken Construction Ltd | Construction | 2026 |
| Aivana Consultancy Ltd | Information & communication | 2025 |
| AIY Properties Ltd | Real estate | 2023 |
| Aiyanna London Ltd | Wholesale & retail | 2022 |
| Aiyla Enterprise Ltd | Health & social care | 2022 |
| Aizatron Ltd | Manufacturing | 2022 |
| Aizel Cabs Ltd | Transport & logistics | 2020 |
| Aizza Holdings Ltd | Financial services | 2026 |
| AJ & Co Traders Ltd | Wholesale & retail | 2025 |
| AJ & EK Properties Limited | Real estate | 2017 |
| AJ & Sons (Leic) Ltd | Wholesale & retail | 2023 |
| AJ Automation Ltd | Administrative & support | 2024 |
| AJ Brothers Construction Limited | Construction | 2020 |
| AJ Carz Limited | Wholesale & retail | 2024 |
| AJ Corparate Ltd | Real estate | 2023 |
| AJ Cosy Nest Limited | Real estate | 2025 |
| AJ Curtis Property Ltd | Real estate | 2025 |
| AJ Estates Student Lets Ltd | Real estate | 2025 |
| AJ Fleet Services Ltd | Manufacturing | 2026 |
| AJ Fresh Fruit and VEG Ltd | Wholesale & retail | 2026 |
| AJ Investment Midlands Ltd | Real estate | 2024 |
| AJ Legal Consultancy Ltd | Professional & scientific | 2024 |
| AJ Nail Spa & Beauty Salon Ltd | Other services | 2021 |
| AJ National Property Ltd | Households | 2025 |
| AJ Property Collective Ltd | Hospitality | 2025 |
| AJ Retail and Fuel Ltd | Wholesale & retail | 2025 |
| AJ Services CH Limited | Construction | 2025 |
| AJ Services ENG Limited | Professional & scientific | 2014 |
| AJ Technology Solutions Ltd | Information & communication | 2025 |
| AJ Truck Ltd | Transport & logistics | 2024 |
| AJ Vision Ltd | Professional & scientific | 2024 |
| Aj's Discount Outlet Ltd | Wholesale & retail | 2024 |
| AJ26 Ltd | Transport & logistics | 2025 |
| AJ360SNAP Ltd | Other services | 2025 |
| AJ91 Investment Ltd | Financial services | 2026 |
| AJA Construction Materials Limited | Construction | 2025 |
| Aja-Ndams Care Services Ltd | Health & social care | 2018 |
| Ajacent Ltd | Professional & scientific | 2019 |
| Ajam Limited | Wholesale & retail | 2023 |
| Ajang Niwas Ltd | Real estate | 2024 |
| AJB Residential Ltd | Real estate | 2025 |
| AJC Civils and Projects Ltd | Construction | 2023 |
| AJC Elevators Limited | Construction | 2013 |
| Ajcs Roofing Ltd | Construction | 2021 |
| AJD Accountancy Services Limited | Professional & scientific | 2005 |
| AJD Consulting Limited | Professional & scientific | 2015 |
| Ajdam Ltd | Real estate | 2023 |
| Ajemiri Neurotech Ltd | Manufacturing | 2025 |
| Ajexia Limited | Wholesale & retail | 2026 |
| AJG Security Services Ltd | Administrative & support | 2022 |
| AJG Wealth Ltd | Financial services | 2015 |
| AJH Electrical Services Leicester Ltd | Manufacturing | 2020 |
| AJH Enterprises Ltd | Wholesale & retail | 2023 |
| Ajit Gurdev Limited | Real estate | 2025 |
| Ajit Transit Ltd | Transport & logistics | 2025 |