| Ackroyd and Harvey Limited | Arts & recreation | 2013 |
| Acquis Holdco Limited | Financial services | 2024 |
| Acquis Limited | Professional & scientific | 1991 |
| Acquis Management Limited | Real estate | 2019 |
| Action House Childcare Limited | Health & social care | 2018 |
| Active Rubbish Clearance Ltd | Water & waste | 2017 |
| Adapt Furniture Limited | Manufacturing | 2014 |
| Aden Media Ltd | Professional & scientific | 2021 |
| Ader Court Limited | Households | 2008 |
| Adrian Hancox Limited | Professional & scientific | 2014 |
| ADV (UK) Limited | Construction | 1999 |
| Advance HR & Training Limited | Professional & scientific | 2006 |
| Advantage Estates Limited | Real estate | 2000 |
| Adveho Limited | Transport & logistics | 2015 |
| Adventure & Computer Holidays Limited | Hospitality | 1985 |
| Adventure Tutoring Ltd | Education | 2023 |
| Aero Optimal Limited | Professional & scientific | 2006 |
| Affinity Angels Limited | Administrative & support | 2010 |
| Affirm Lgbt Limited | Education | 2022 |
| Agarwal Associates Limited | Information & communication | 1986 |
| Agency X Services Limited | Administrative & support | 2024 |
| Agent Access Ltd | Professional & scientific | 2026 |
| Agmondesham Ltd | Transport & logistics | 2018 |
| Agxio Limited | Information & communication | 2018 |
| AIM Risk Services Limited | Financial services | 2012 |
| Aiqos Limited | Information & communication | 2021 |
| Airlingua International Ltd | Education | 2014 |
| AJ Spindles Ltd | Other services | 2026 |
| AJP Advisory Limited | Professional & scientific | 2019 |
| AK Campervans Limited | Manufacturing | 2018 |
| AKB Contractors Limited | Water & waste | 2003 |
| Alan Grové Creative Ltd. | Professional & scientific | 2023 |
| Albany Court Residents Company Limited | Households | 2003 |
| Albion Cleaning Services Limited | Administrative & support | 2022 |
| Albori Consulting Limited | Information & communication | 2014 |
| Alder Grove Chilworth Management Company Limited | Construction | 2018 |
| Aldhurst Military Vehicles Limited | Administrative & support | 2015 |
| Alex Cliff Limited | Health & social care | 2016 |
| Alex Miller Book-Keeping Services Limited | Professional & scientific | 2002 |
| Alexander Dork Limited | Wholesale & retail | 2026 |
| Alison Hall & Associates Limited | Administrative & support | 2015 |
| Alivia Associates Limited | Other services | 2005 |
| ALL Property UK Limited | Real estate | 1988 |
| ALL Things Creative Ltd | Arts & recreation | 2013 |
| Allan G. Hill & Partners Limited | Professional & scientific | 2001 |
| Allied Portland Estates Limited | Real estate | 1996 |
| Allude Agency Limited | Extraterritorial | 2020 |
| Allware Systems Limited | Information & communication | 2001 |
| Alpha Mike Tours Limited | Administrative & support | 1979 |
| Alpine Court Freehold Limited | Households | 1997 |
| Alvaston (Guildford) Residents Association Limited | Households | 2022 |
| Alvik Consulting Limited | Information & communication | 2015 |
| Amadeus Aviation Limited | Professional & scientific | 2002 |
| Amazyn Healthcare Ltd | Health & social care | 2021 |
| Amazyn Professionals Ltd | Health & social care | 2018 |
| Amber Dermacare Limited | Other services | 2022 |
| Amber Sky Training Ltd. | Professional & scientific | 2015 |
| Ambercity Limited | Real estate | 2016 |
| AMTS2 Associates Ltd | Professional & scientific | 2025 |
| Amuseio Limited | Information & communication | 2018 |
| AMY Court Limited | Real estate | 1996 |
| Analogue Dog Ltd | Professional & scientific | 2018 |
| Anandpb Limited | Information & communication | 2014 |
| Anbridge Consulting Limited | Professional & scientific | 2015 |
| Anderson Hearn Keene Limited | Professional & scientific | 1994 |
| Angel Office Village Limited(The) | Real estate | 1986 |
| Angelika C.J. Friebe Limited | Wholesale & retail | 1997 |
| Angell Consulting Limited | Professional & scientific | 2011 |
| Anissa Helou Limited | Professional & scientific | 2013 |
| Annie Lois Design Ltd | Professional & scientific | 2014 |
| Anointed Scents Ltd | Manufacturing | 2024 |
| Another String Limited | Administrative & support | 2014 |
| Ansell Group Risk Consulting Ltd | Financial services | 2024 |
| Anstie Grange Management Company Limited | Real estate | 2008 |
| Anstiebury GAS Services Limited | Professional & scientific | 2020 |
| ANT Evolution Ltd | Construction | 2024 |
| Anthony Wakefield and Company Limited | Financial services | 1983 |
| Antylles Limited | Professional & scientific | 2015 |
| Anxplace Limited | Education | 2023 |
| Apcentric Ltd | Information & communication | 2000 |
| Apecc Limited | Information & communication | 2023 |
| Apex Litigation Support Ltd | Administrative & support | 2024 |
| Appd & C Co. Ltd. | Construction | 2011 |
| Aptivis Limited | Professional & scientific | 2006 |
| Aquatic Agents Ltd | Professional & scientific | 2021 |
| Aragorn Place Residents Company Limited | Households | 2003 |
| ARB Consultancy Trees Limited | Agriculture & fishing | 2014 |
| ARC Project Prism Limited | Real estate | 2024 |
| Arcadia Construction (Horsham) Ltd. | Construction | 2010 |
| Archon Management Services Ltd | Construction | 2012 |
| Archway Mews Residents' Association Limited | Households | 1984 |
| Arctic Experience Limited | Administrative & support | 1984 |
| Ardent Paving Ltd | Administrative & support | 2023 |
| Arena (Southern) Developments Ltd | Construction | 2005 |
| Argentine Steakhouse (Bidco) Limited | Hospitality | 2022 |
| Argyll Shipping Limited | Transport & logistics | 2002 |
| Aries Digital Ltd | Professional & scientific | 2020 |
| Arika Consulting Limited | Administrative & support | 2013 |
| Arrack Dorking Limited | Hospitality | 2025 |
| Array Sound Ltd | Manufacturing | 2020 |