| Able-X Consulting Limited | Professional & scientific | 2007 |
| About Care Limited | Health & social care | 2022 |
| Absolute Beds Limited | Extraterritorial | 2007 |
| AC Food Ltd | Hospitality | 2022 |
| Academy of Arts and Antiques Stewardship Ltd | Education | 2026 |
| Accelerance U.K. Ltd. | Professional & scientific | 2016 |
| Access Metals Ltd | Wholesale & retail | 2025 |
| Accord Accountants - Hampton Hill Limited | Professional & scientific | 2002 |
| Ace Trading Enterprises Limited | Real estate | 2010 |
| Ace Web Curator Limited | Information & communication | 2025 |
| ACP UK Investment Ltd | Real estate | 2017 |
| Acro Consulting Limited | Information & communication | 2021 |
| Active Kids Learn LLP | | 2023 |
| Active Life Podiatry Limited | Health & social care | 2008 |
| ADA Special Limited | Wholesale & retail | 2023 |
| Adams Asset Ltd | Real estate | 2020 |
| ADC Stars Ltd | Administrative & support | 2016 |
| Addison Bradley Consulting Ltd | Professional & scientific | 2026 |
| Advance Business Training Limited | Education | 2002 |
| Adventure Travel Networking Ltd | Administrative & support | 2019 |
| Aegis Talent Ltd | Administrative & support | 2023 |
| Aegis Ventures Ltd | Real estate | 2018 |
| Africana Women S.H.I.N.E.S CIC | Professional & scientific | 2026 |
| Africompli UK Ltd | Information & communication | 2026 |
| AGE UK Richmond Services Limited | Health & social care | 2013 |
| AGE UK Richmond Upon Thames | Health & social care | 2000 |
| Agile Apex Ltd | Information & communication | 2023 |
| Agile for HR Ltd | Extraterritorial | 2021 |
| Agile Housing Solutions Ltd | Professional & scientific | 2016 |
| Agile Human Resources Ltd | Extraterritorial | 2021 |
| AGM Project Management Consulting Limited | Information & communication | 2024 |
| Agrikron UK Limited | Financial services | 2023 |
| Ahearn Construction Limited | Construction | 2009 |
| Ahearn Properties Limited | Real estate | 2016 |
| Aigens Global Limited | Real estate | 2018 |
| Air Associates Limited | Construction | 1967 |
| AIT Systems Limited | Manufacturing | 2005 |
| Aj&G Property Ltd | Real estate | 2020 |
| AJC Property Solutions Ltd | Real estate | 2021 |
| AK Sprayed Joinery Ltd | Construction | 2015 |
| AL Wellness Ltd | Health & social care | 2024 |
| Albion House (Station Road) Management Limited | Households | 2017 |
| Aldenham Estates Limited | Real estate | 2000 |
| Aldershot Trust Estates Limited | Real estate | 1934 |
| Aldia (Holdings) Limited | Extraterritorial | 2012 |
| Aldia Limited | Real estate | 1983 |
| Alex Enterprises Ltd | Hospitality | 2003 |
| Alexa Investments Ltd | Real estate | 2017 |
| Alfasapp IT Ltd | Information & communication | 2020 |
| Alice & Francis Properties Ltd | Real estate | 2018 |
| Alice and Oliver Ltd | Real estate | 2019 |
| Align Yoga & Pilates Ltd | Education | 2022 |
| Alimentum Holdings Ltd | Extraterritorial | 2019 |
| ALL Action Props Ltd | Information & communication | 2022 |
| Allushi Builders Ltd | Construction | 2026 |
| Almo Property Group Limited | Construction | 2025 |
| Aloa Events Limited | Arts & recreation | 2023 |
| Aloa Lighting Ltd | Arts & recreation | 2023 |
| Alok Automobiles Limited | Wholesale & retail | 2024 |
| Alpha Baxter Ltd | Agriculture & fishing | 2020 |
| Alphametric Solutions Ltd | Financial services | 2009 |
| Alsayed Greengrocer Ltd | Wholesale & retail | 2025 |
| Alsim System Building Limited | Financial services | 2022 |
| Altee Investments Ltd | Extraterritorial | 2019 |
| Alternative Capital Advisors Limited | Extraterritorial | 2015 |
| Alternative Landscape Gardens Ltd | Administrative & support | 2021 |
| Alvis & Company (Accountants) Ltd. | Professional & scientific | 2002 |
| Am&C Media Limited | Other services | 2023 |
| Amabrands Ltd. | Professional & scientific | 2023 |
| Amac Boat Repairs Ltd | Manufacturing | 2017 |
| Amalgamated Holdco Limited | Real estate | 2015 |
| Amamus Ltd | Wholesale & retail | 2011 |
| Amariss Limited | Health & social care | 2021 |
| Amateur Darts Circuit Ltd | Professional & scientific | 2020 |
| Amazing Choice Ltd | Real estate | 2017 |
| Amcollective Ltd | Other services | 2016 |
| Amdm Delivery Solutions Ltd | Transport & logistics | 2024 |
| Amedar Company Limited | Real estate | 2016 |
| AMF Affinity Limited | Health & social care | 2024 |
| Amhest Partners Ltd | Real estate | 2022 |
| Amour Investments Limited | Real estate | 2025 |
| Analyst Services Ltd | Information & communication | 2002 |
| Andrea Bond Ltd | Information & communication | 2014 |
| Andrei Batchkar Ltd | Extraterritorial | 2024 |
| Andrew Leader Ltd | Other services | 2003 |
| Anew Clinics Ltd | Health & social care | 2018 |
| Angel Falls Ltd | Health & social care | 2010 |
| Anglesea House(Kingston-Upon-Thames)Residents Association Limited | Households | 1964 |
| Anvisiya Ltd | Hospitality | 2025 |
| Apjc Trading Limited | Construction | 2019 |
| Appleby Connect Limited | Administrative & support | 2017 |
| APT Studio Ltd | Information & communication | 2023 |
| Aquarius Riverside Limited | Households | 1975 |
| Aranya Futuregrove Property Management Ltd | Real estate | 2026 |
| Arayn K Properties LLP | | 2021 |
| Arayn T Properties Limited | Real estate | 2021 |
| ARC Shene Consulting Ltd | Professional & scientific | 2019 |
| Arc-En-Ciel Consultancy Ltd | Administrative & support | 2004 |
| Arca Bespoke Furniture Ltd | Manufacturing | 2020 |
| Arch Empire Limited | Real estate | 2018 |