| Abidapt Limited | Construction | 2018 |
| Aboundantly Able Services Limited | Health & social care | 2013 |
| ABP & SON Limited | Real estate | 2019 |
| Abps Limited | Professional & scientific | 2004 |
| ABS Care Ltd | Health & social care | 2020 |
| Abstraction Works Ltd | Information & communication | 2025 |
| ABV Network Ltd | Wholesale & retail | 2018 |
| ABY Housing Ltd | Other services | 2021 |
| Abyj Ltd | Real estate | 2021 |
| AC Health & Nutrition Services Ltd | Health & social care | 2020 |
| AC Thomas Limited | Education | 2021 |
| Access to Bitcoin Ltd | Information & communication | 2025 |
| Access Visa Services Ltd | Extraterritorial | 2025 |
| Accounting Solution (London) Limited | Professional & scientific | 2012 |
| Ace Labs Ltd | Wholesale & retail | 2018 |
| Aceley Home Ltd | Wholesale & retail | 2025 |
| ACI Oilfield Services Limited | Mining & quarrying | 2026 |
| ACT4HOME Ltd | Construction | 2003 |
| Action Isleworth Mothers (AIM) Ltd | Health & social care | 2023 |
| Activating Change Ltd | Professional & scientific | 2017 |
| Active Data Insights Limited | Information & communication | 2019 |
| Active Voices Limited | Information & communication | 2022 |
| Acton Lane 377 Limited | Real estate | 2008 |
| Acton Lane Medical Centre Limited | Health & social care | 2020 |
| AD Meliora Ltd | Health & social care | 2016 |
| Adaab Hyderabad Ltd | Hospitality | 2024 |
| Adam Brave Ltd | Wholesale & retail | 2016 |
| Adam Van Ltd | Transport & logistics | 2017 |
| Adapt Ventures Limited | Wholesale & retail | 2013 |
| Adaptax Investments Ltd | Financial services | 2025 |
| Adaptax Ltd | Professional & scientific | 2018 |
| ADC Atelier Ltd | Professional & scientific | 2021 |
| Adcraft Digital Ltd | Information & communication | 2025 |
| ADD Catering Ltd | Hospitality | 2025 |
| ADD Network Ltd | Construction | 2023 |
| Add-Com Ltd. | Information & communication | 2009 |
| Addison Trimz Ltd | Other services | 2020 |
| Addwater Properties Ltd | Real estate | 2024 |
| Adfr Limited | Extraterritorial | 2020 |
| Adini Fashion LLP | | 2008 |
| ADM Packaging Supplies UK Ltd | Administrative & support | 2012 |
| Admedia Impact Ltd | Professional & scientific | 2025 |
| Admic Limited | Financial services | 2023 |
| Adnanprecise Ltd | Wholesale & retail | 2025 |
| Adorgusco Properties Limited | Real estate | 2013 |
| Adqua Ltd | Professional & scientific | 2019 |
| Adrian Building Ltd | Construction | 2022 |
| Adsukds Ltd | Construction | 2025 |
| Advanced Agencies Limited | Real estate | 2019 |
| Advanced Air Conditioning Limited | Construction | 2007 |
| Adviga Ltd | Health & social care | 2023 |
| Adwo Ltd | Construction | 2010 |
| ADZ Professional Limited | Administrative & support | 2021 |
| Ae-Codekidz UK Ltd | Education | 2018 |
| AEI Corporation Limited | Wholesale & retail | 2019 |
| Aesthetix Clinic Limited | Health & social care | 2015 |
| Afgani Bakery Ltd | Manufacturing | 2023 |
| African Palms Limited | Wholesale & retail | 1984 |
| AFS Autoworks Ltd | Wholesale & retail | 2023 |
| AFZ Traders Ltd | Wholesale & retail | 2024 |
| AG Football Limited | Education | 2023 |
| Agentic Networks Ltd | Administrative & support | 2026 |
| Aggc Property Limited | Real estate | 2016 |
| Agha and Banoo Ltd. | Wholesale & retail | 2017 |
| Agile Analytics Consulting Ltd | Information & communication | 2021 |
| Agreed Voices Limited | Information & communication | 2020 |
| Ahfia Properties Limited | Real estate | 2018 |
| Ahmad Sultan Design Limited | Wholesale & retail | 2022 |
| Ahmedia (Global Consulting) Limited | Professional & scientific | 2025 |
| Ahsf Ltd | Extraterritorial | 2021 |
| AI Embrace Ltd | Information & communication | 2026 |
| AI Fitters Limited | Information & communication | 2026 |
| AI Heroes Limited | Information & communication | 2022 |
| AI Pioneers Ltd | Information & communication | 2024 |
| AI Property Investments Limited | Real estate | 2025 |
| Aiden Construct Ltd | Construction | 2025 |
| Aidicose Construction Ltd | Construction | 2025 |
| AIM Extra Mile Ltd | Transport & logistics | 2019 |
| Aiman Worktop Limited | Manufacturing | 2025 |
| Air Construction Ltd | Construction | 2013 |
| Aishwarya Nest Living Ltd | Real estate | 2025 |
| AJ Audiology Ltd | Health & social care | 2025 |
| AJC IT Consulting Limited | Information & communication | 2023 |
| Ajyo Partners Limited | Health & social care | 2025 |
| AK Building and Property Services Ltd | Construction | 2019 |
| AK Creations 07 Ltd | Professional & scientific | 2023 |
| AK Double Glazing Ltd | Construction | 2026 |
| Ak&J Ltd | Construction | 2016 |
| Ak.Makans Ltd | Real estate | 2024 |
| Akella Associates Ltd | Real estate | 2016 |
| Akhan Properties (UK ) Limited | Real estate | 2023 |
| Akkad Essence Ltd | Real estate | 2020 |
| Aklest.Com Ltd | Wholesale & retail | 2020 |
| Akme Estates Ltd | Real estate | 2023 |
| AKN Tech Solutions Ltd | Information & communication | 2018 |
| AL Media Services Ltd | Information & communication | 2021 |
| Al-Fakher Europe Ltd | Wholesale & retail | 2009 |
| Al-Fakher London Supplies Ltd | Wholesale & retail | 2010 |
| Alam London Limited | Wholesale & retail | 2023 |
| Albert Luncarty Limited | Professional & scientific | 2018 |