| Accounts on Sea Limited | Professional & scientific | 2017 |
| Aces Executive Tours and Transfers Limited | Transport & logistics | 2025 |
| Acme Developments (London) Ltd | Real estate | 2023 |
| Acme Developments (UK) Ltd | Real estate | 2006 |
| Acme Investments (Essex) Limited | Real estate | 2024 |
| Active TC Limited | Information & communication | 2025 |
| AD Photo Studio Ltd | Professional & scientific | 2011 |
| AD Tennis LLP | | 2018 |
| ADI & Aiden Ltd | Wholesale & retail | 2020 |
| Adonia Boutique Hammam Spa Limited | Other services | 2023 |
| Adovys Limited | Information & communication | 2019 |
| Adrian Contractors Ltd | Construction | 2020 |
| Adtekh IT Ltd | Information & communication | 2025 |
| Adtekh Limited | Other services | 2017 |
| Advanced Aspect Roofing Ltd | Construction | 2021 |
| Advanced Assembling Ltd | Manufacturing | 2025 |
| Advanced Facilities Management Ltd | Construction | 2024 |
| Affiliate 23 Limited | Professional & scientific | 2022 |
| Affinity Catering Limited | Hospitality | 2006 |
| African Taste Restaurant Limited | Hospitality | 2016 |
| AFS Plant Hire Ltd | Administrative & support | 2016 |
| AG Medics Ltd | Health & social care | 2024 |
| Agathe Skalli Interiors Limited | Wholesale & retail | 2026 |
| AGB Swordplay Ltd | Education | 2022 |
| Agency for Creative Production CIC | Education | 2022 |
| Agenda Medical Locums Limited | Administrative & support | 2004 |
| AHM Accountants & Tax Consultants Ltd | Professional & scientific | 2023 |
| AI for Global Health CIC | Education | 2026 |
| Aiforgetech Ltd | Wholesale & retail | 2026 |
| Aimdex Tiling Ltd | Construction | 2017 |
| Airnoly Ltd | Manufacturing | 2022 |
| AJ Motorparts Ltd | Wholesale & retail | 2025 |
| AJ Motorsport Tuning Ltd | Professional & scientific | 2021 |
| AJD Transport Ltd | Transport & logistics | 2017 |
| Ajmd Research Ltd | Professional & scientific | 2023 |
| AJR Consultants Ltd | Information & communication | 2019 |
| AKG Packaging Ltd | Administrative & support | 2022 |
| AKG UK Packaging Limited | Wholesale & retail | 2023 |
| Al-Bharaka 786 Properties Ltd | Real estate | 2025 |
| Albert Thai Food Ltd | Hospitality | 2017 |
| Albinas Services Ltd | Other services | 2020 |
| Albion Fenestration Ltd | Manufacturing | 2025 |
| Aleks Traders Limited | Construction | 2025 |
| Alex Barber 2 Ltd | Other services | 2023 |
| Alexander James Real Estate Limited | Real estate | 2025 |
| Alexander Office Ltd | Real estate | 2022 |
| Alfie's Fish-On-Sea Ltd | Hospitality | 2025 |
| ALG Executive Search Ltd | Administrative & support | 2025 |
| Algo Limited | Professional & scientific | 2018 |
| Alijainvestments Ltd | Hospitality | 2021 |
| ALL HOP Ltd | Wholesale & retail | 2024 |
| ALL Your Needs Limited | Wholesale & retail | 2005 |
| Alliance Energy Ltd | Wholesale & retail | 2022 |
| Alliance Financial Solutions Limited | Construction | 2006 |
| Alpine Electrical Services Limited | Construction | 2003 |
| Alvaros Restaurant Limited | Hospitality | 2025 |
| Always Live Ltd | Arts & recreation | 2019 |
| Amaj Consultancy Limited | Professional & scientific | 2025 |
| Amazx Ltd | Wholesale & retail | 2023 |
| Amey MAP Services Limited | Energy | 2017 |
| Ameya Limited | Wholesale & retail | 2012 |
| Amor Holiday Limited | Real estate | 2021 |
| Andesphere Ltd | Information & communication | 2025 |
| Andrew Beevers Sports Ventures Ltd | Arts & recreation | 2010 |
| Andrew Oakey Post Ltd | Information & communication | 2022 |
| Andrews Wealth Ltd | Professional & scientific | 2017 |
| Anerley Holdings Limited | Real estate | 2018 |
| Anerley Road Ltd | Real estate | 2021 |
| Angel International Repatriation Ltd | Other services | 2021 |
| Angiebluemonkey Limited | Professional & scientific | 2026 |
| Anitamaradesa Limited | Public administration | 2025 |
| Anna Tahsin Mortgages and Protection Ltd | Financial services | 2024 |
| Ansh Consultancy Ltd | Information & communication | 2023 |
| Answercafe Ltd | Wholesale & retail | 2021 |
| AOK Enterprises Ltd | Wholesale & retail | 2016 |
| APH Accountancy Services Limited | Professional & scientific | 2012 |
| Applecheck Services Limited | Extraterritorial | 2012 |
| Appleglaze Limited | Hospitality | 2018 |
| Appleolive Limited | Hospitality | 2026 |
| Applifting Digital Limited | Information & communication | 2020 |
| Appzeal Technologies Limited | Information & communication | 2012 |
| Aqro Construction Limited | Real estate | 2023 |
| Aqua LOO Toilet Hire Ltd | Administrative & support | 2021 |
| Aquachina Limited | Hospitality | 2019 |
| ARC Networks Solutions Ltd | Information & communication | 2025 |
| Arcade Recruitment Training Ltd | Administrative & support | 2024 |
| Arcade Tiling Limited | Construction | 2018 |
| Arch TEN Limited | Real estate | 2025 |
| Archer Management Services Limited | Construction | 2016 |
| Arden (Brentwood) Management Limited | Households | 2004 |
| Argyll House Flats Management Co. (Westcliff-On-Sea) Limited | Households | 1973 |
| Ariana Transport Ltd | Transport & logistics | 2017 |
| Ariun Ltd | Agriculture & fishing | 2023 |
| ARK Compliance Ltd | Construction | 2024 |
| ARK Management Group Limited | Real estate | 2017 |
| Aron Shop Ltd | Real estate | 2020 |
| Arosh Finance Ltd | Financial services | 2018 |
| Arosh Limited | Financial services | 2017 |
| Arosproperty Limited | Real estate | 2023 |
| Arowosaye Bags Ltd | Wholesale & retail | 2026 |