| Agri Group Holdings Ltd | Manufacturing | 2026 |
| Agri Incineration Systems Limited | Manufacturing | 2021 |
| Agricultural Recruitment Specialists Limited | Administrative & support | 2012 |
| Agriculture Live Ltd | Professional & scientific | 2023 |
| Agrotura Ltd | Professional & scientific | 2024 |
| AHM Services Limited | Construction | 2024 |
| AI Holdings Limited | Professional & scientific | 2018 |
| AI Management Consultancy Limited | Professional & scientific | 2014 |
| AI1 Aesthetics Ltd | Other services | 2022 |
| AI1 Wellness Ltd | Other services | 2026 |
| AIP Amarya Limited | Professional & scientific | 2011 |
| Air Liquide Healthcare Limited | Health & social care | 1988 |
| Airband Community Internet Limited | Information & communication | 2009 |
| Airband Limited | Information & communication | 2011 |
| Airband Topco Limited | Financial services | 2021 |
| Airducts Design Limited | Manufacturing | 1998 |
| AJ MHL Holdings Limited | Real estate | 2025 |
| AJB Medical Services Ltd | Health & social care | 2020 |
| AJG Property Portfolio Limited | Real estate | 2023 |
| Ajjl Limited | Construction | 2022 |
| AJS Restorative Ltd | Health & social care | 2023 |
| Akamas Holiday Properties Limited | Hospitality | 2016 |
| Akari Group Limited | Administrative & support | 2016 |
| AKC Oncology Limited | Health & social care | 2017 |
| AKH Renovations Limited | Real estate | 2025 |
| AL and Pals Marketing Consultancy Ltd | Professional & scientific | 2025 |
| Alcema Construction Limited | Construction | 2023 |
| Alcema Developments Limited | Professional & scientific | 2023 |
| Alcema Fire Safety Limited | Administrative & support | 2010 |
| Alcema Ltd | Construction | 2016 |
| Alcema Plant Limited | Other services | 2023 |
| Alcema Projects Limited | Professional & scientific | 2023 |
| Alcema Services Limited | Professional & scientific | 2023 |
| Alcester Properties Limited | Real estate | 1998 |
| Aldridge Family Investments Limited | Financial services | 2023 |
| Aleafia Ltd | Health & social care | 2019 |
| Alka Enterprise Limited | Real estate | 2019 |
| Alkenny Essentials Ltd | Wholesale & retail | 2022 |
| ALL Cleaning Solutions Ltd. | Administrative & support | 2022 |
| ALL Crafts Connect Ltd | Information & communication | 2025 |
| ALL in One Beauty Ltd | Other services | 2023 |
| ALL Seasons by GG Ltd | Wholesale & retail | 2021 |
| Allen Construction Management Limited | Construction | 2011 |
| Alliance Payroll Services Limited | Professional & scientific | 2005 |
| Allison's Kitchen Limited | Wholesale & retail | 2006 |
| Allseasonsgwr Ltd | Administrative & support | 2024 |
| Allswage UK Properties Limited | Professional & scientific | 2010 |
| Alpha Block Capital Limited | Information & communication | 2021 |
| Alpha Group Holdings Limited | Manufacturing | 2021 |
| Alpha Shopfitting Ltd | Construction | 2018 |
| Alpha-Immunotech Healthcare Ltd | Health & social care | 2024 |
| Alpha-Liberi Healthcare Ltd | Health & social care | 2023 |
| ALS Kingfisher Limited | Administrative & support | 2017 |
| Alsinstallations Limited | Extraterritorial | 2012 |
| Altered Images Physiotherapy Limited | Health & social care | 2003 |
| Altogetherautism Ltd | Education | 2026 |
| Altru Group Ltd | Financial services | 2026 |
| Altru Solutions Ltd | Administrative & support | 2026 |
| Altura Independent School Ltd | Education | 2025 |
| Alumni Sport Ltd | Manufacturing | 2025 |
| Alvechurch Gymnastics Club Limited | Arts & recreation | 2025 |
| Amaxmo Lettings Limited | Real estate | 2020 |
| Amaxmo Limited | Wholesale & retail | 2006 |
| Amaxmo Renovations Limited | Construction | 2009 |
| Amaya Medical Limited | Health & social care | 2010 |
| Amazon Steels Ltd | Professional & scientific | 2023 |
| Ambassador Close Management Company Limited | Households | 1977 |
| Amber (West Mids) Limited | Real estate | 2022 |
| Ambient Air Conditioning Limited | Administrative & support | 2004 |
| Ambleside Solihull Restaurant and Garden Centre Limited | Wholesale & retail | 2023 |
| AMF Solutions Limited | Administrative & support | 2017 |
| Amiee Leeson Transport Ltd | Transport & logistics | 2020 |
| Amplify Hire Tech Limited | Administrative & support | 2025 |
| Amre Group Ltd | Administrative & support | 2024 |
| Amre Holdings Limited | Administrative & support | 2021 |
| AMT Commercial Limited | Professional & scientific | 2017 |
| Amtah Ltd | Health & social care | 2015 |
| AMY Lennox Productions Limited | Arts & recreation | 2015 |
| Andrew DEY Financial Services Limited | Financial services | 2019 |
| Animal Innovations Ltd | Administrative & support | 2024 |
| Ansell Developments Limited | Construction | 2014 |
| Anston Stonework Ltd | Construction | 2022 |
| Anthony Champion Limited | Professional & scientific | 2021 |
| Anypalletanywhere.Com Ltd | Transport & logistics | 2023 |
| Apatan Productions Ltd | Information & communication | 2018 |
| Apeiron Stays Limited | Real estate | 2022 |
| Apex Fitting Solutions Ltd | Professional & scientific | 2026 |
| Apex Office Solutions Limited | Administrative & support | 2016 |
| Aphex Engineering & Fabrication Services Limited | Construction | 2016 |
| APJ2 Diagnostics Ltd | Health & social care | 2025 |
| APM Services (Midlands) Ltd | Real estate | 2024 |
| Apogee Academia Limited | Information & communication | 2019 |
| Apollo 77 Projects Limited | Real estate | 2020 |
| Apparition Content Ltd | Professional & scientific | 2025 |
| Apple Tree House Investments Limited | Financial services | 2019 |
| Applecross Equestrian Limited | Agriculture & fishing | 2015 |
| Applied Scripted ARC Ltd | Arts & recreation | 2025 |
| Applied Scripted ARC Projects CIC | Education | 2025 |
| Appoint Ltd | Administrative & support | 2026 |
| Apricus Decor Ltd | Wholesale & retail | 2022 |