| Andover Home Improvements Limited | Administrative & support | 2015 |
| Andover Home Solutions Ltd | Construction | 2023 |
| Andover Informatics Limited | Real estate | 2016 |
| Andover Kebab & Pizza House Ltd | Hospitality | 2021 |
| Andover Lawn Tennis Club Limited | Arts & recreation | 2016 |
| Andover Marlborough Winchester Auctions Limited | Real estate | 2016 |
| Andover Martial Arts and Fitness Centre Limited | Arts & recreation | 2012 |
| Andover Masonic Hall Limited | Real estate | 1970 |
| Andover Mind | Health & social care | 1994 |
| Andover Mini Storage Limited | Administrative & support | 2007 |
| Andover Motorcycles Limited | Wholesale & retail | 2022 |
| Andover Norton International Limited | Manufacturing | 1995 |
| Andover Offlicence PVT Ltd | Wholesale & retail | 2018 |
| Andover Pallet Solutions Limited | Transport & logistics | 2020 |
| Andover Physiotherapy Ltd | Health & social care | 2011 |
| Andover Primary Care Network Limited | Health & social care | 2023 |
| Andover Printing Company Limited | Manufacturing | 2002 |
| Andover Radio Limited | Information & communication | 2015 |
| Andover Radio Mono | Information & communication | 2023 |
| Andover Resin Ltd | Construction | 2024 |
| Andover Rubber Stamp Service Limited | Manufacturing | 1975 |
| Andover Salto Gymnastics Club Limited | Arts & recreation | 1993 |
| Andover Solar Park Limited | Energy | 2013 |
| Andover Sushi Limited | Wholesale & retail | 2025 |
| Andover Tachograph Centre Limited | Wholesale & retail | 2010 |
| Andover Timber Company Ltd | Wholesale & retail | 2017 |
| Andover Town Centre BID Limited | Other services | 2018 |
| Andover Trail Events Limited | Arts & recreation | 2019 |
| Andover Truck and Van Ltd. | Wholesale & retail | 2018 |
| Andover Tyre and Auto Services Limited | Wholesale & retail | 2009 |
| Andover West Chinese Ltd | Hospitality | 2023 |
| Andrews Law Consultancy Ltd | Other services | 2024 |
| Aneto Education and Training Group Ltd | Education | 2021 |
| Angel Call Handling Ltd | Information & communication | 2017 |
| Angell Law Limited | Professional & scientific | 2025 |
| Angelo Trans Ltd | Transport & logistics | 2018 |
| Angelproof Ltd | Administrative & support | 2014 |
| Anglomile Investments Limited | Real estate | 2018 |
| Anjake Vapes Limited | Wholesale & retail | 2023 |
| Ansh Superstore Ltd | Wholesale & retail | 2020 |
| Antiference Window Systems Ltd | Manufacturing | 2025 |
| Anton Management Company Limited | Households | 1983 |
| Anushree Catering Services Ltd | Hospitality | 2022 |
| Apex Fennell Dynamics Ltd | Professional & scientific | 2025 |
| Apex Precision Holdings Ltd | Manufacturing | 2025 |
| Apexward Consulting LLP | | 2026 |
| Apocryf Ltd | Transport & logistics | 2017 |
| Apogee Lead Roofing Limited | Construction | 2003 |
| Apple Admin Ltd | Administrative & support | 2023 |
| Appleshaw Ventures Limited | Professional & scientific | 2025 |
| April's Farm Ltd | Health & social care | 2018 |
| Apsley Farms Group Limited | Financial services | 2023 |
| Apsley Farms Holdings Limited | Real estate | 2026 |
| Apsley Farms Sales Limited | Agriculture & fishing | 2021 |
| Apsley Farms Services Limited | Administrative & support | 2024 |
| Aqua Lounge Ltd | Wholesale & retail | 2024 |
| Aquercus Property Ltd | Real estate | 2022 |
| ARC Events Creative Limited | Hospitality | 2019 |
| ARC Events Limited | Administrative & support | 2011 |
| Arceus Window Cleaning Ltd | Administrative & support | 2023 |
| Archer Advisors Ltd | Professional & scientific | 2019 |
| Archie Parker Limited | Wholesale & retail | 2024 |
| Arco Arts Management Limited | Arts & recreation | 2024 |
| Arena Financial Management Ltd. | Professional & scientific | 2018 |
| Argus 1 Training Limited | Education | 2020 |
| Arise Lifts Ltd | Manufacturing | 2021 |
| Arkhive House Limited | Administrative & support | 2017 |
| Arktos Business Consulting Limited | Professional & scientific | 2024 |
| Arma Autos Andover Limited | Wholesale & retail | 2024 |
| Armala Ltd | Transport & logistics | 2024 |
| Armis International (UK) Limited | Public administration | 2017 |
| Armorduct Limited | Wholesale & retail | 2022 |
| Armorduct Systems Limited | Manufacturing | 1998 |
| Armstrong Rise 1959 Limited | Extraterritorial | 2014 |
| Arniam Limited | Professional & scientific | 2024 |
| Arniam Properties Ltd | Real estate | 2024 |
| Arriavo Ltd | Wholesale & retail | 2013 |
| Artspace Interior Design Limited | Construction | 2006 |
| Aruwon Limited | Professional & scientific | 2011 |
| Aseptick Compliance Limited | Extraterritorial | 2020 |
| Aseptick Limited | Extraterritorial | 2020 |
| Ashbrook (UK) Ltd | Information & communication | 2014 |
| Ashley Barn Projects Ltd | Construction | 2015 |
| Ashwells Estate Agents Limited | Real estate | 2010 |
| Askamillion.Com Limited | Professional & scientific | 2017 |
| ASM Datacore Limited | Information & communication | 2012 |
| ASP Consulting Ltd | Professional & scientific | 2025 |
| Aspen Restoration Limited | Administrative & support | 2012 |
| Aspo Housing Limited | Real estate | 2025 |
| Asriel Limited | Health & social care | 2011 |
| Assetvison Limited | Real estate | 2026 |
| Associated Toys Limited | Transport & logistics | 1981 |
| Assor Limited | Real estate | 2007 |
| Assuage Services Limited | Professional & scientific | 2018 |
| Aster Process and Packaging Ltd | Wholesale & retail | 2018 |
| Astonish Email Limited | Information & communication | 2013 |
| Astra Tech Solution Ltd | Wholesale & retail | 2013 |
| Asya 1302 Ltd | Hospitality | 2023 |
| AT Stepframes Ltd | Extraterritorial | 2001 |
| ATF Supplies Nationwide Limited | Wholesale & retail | 2011 |