| Academy Foodservice Ltd | Wholesale & retail | 2020 |
| Academy of Professional Dialogue | Other services | 2017 |
| Academy Portraits Limited | Professional & scientific | 1998 |
| Academy Sports & Leisure Limited | Wholesale & retail | 2006 |
| Acasta Developments Limited | Arts & recreation | 2012 |
| Acasta Homes Limited | Extraterritorial | 2022 |
| Accelerate Advisory Services Ltd | Information & communication | 2024 |
| Acceleratio Limited | Professional & scientific | 2023 |
| Accelita Limited | Information & communication | 2019 |
| Access 2 Specialists Ltd | Professional & scientific | 2024 |
| Access Associates Limited | Professional & scientific | 2003 |
| Access Contracts Limited | Information & communication | 2012 |
| Accolade Corporate Events Limited | Administrative & support | 2002 |
| Account-Ability Limited | Information & communication | 1998 |
| Accounting for the Future Limited | Professional & scientific | 2003 |
| Accounting Hub Solutions Limited | Professional & scientific | 2024 |
| Acelba (Angèle's Cuisine ET LA Belle Africaine) Limited | Hospitality | 2023 |
| Acer Tree Properties Limited | Real estate | 2018 |
| ACG Financial Limited | Professional & scientific | 2012 |
| ACG Wills & Estate Planning Ltd | Professional & scientific | 2019 |
| Acgl Limited | Manufacturing | 2023 |
| Acheta Consulting Limited | Extraterritorial | 2003 |
| Achievers International Campus Limited | Education | 2025 |
| Achieving Goals Homes Limited | Health & social care | 2023 |
| Achieving Goals Services Limited | Health & social care | 2025 |
| Achieving the Difference Limited | Professional & scientific | 2021 |
| ACL 2007 Ltd | Administrative & support | 2007 |
| Acmb Investments Ltd | Real estate | 2004 |
| Acmb Management Limited | Households | 2026 |
| Acme Coaching Company Ltd | Education | 2019 |
| Acne Antidote Limited | Health & social care | 2023 |
| Acorn Alpha Limited | Information & communication | 2025 |
| Acorn Bookkeeping and Accounts Limited | Professional & scientific | 2017 |
| Acorn Financial Planning Ltd | Financial services | 2013 |
| Acorn Group Pension Admin Ltd | Financial services | 2013 |
| Acorn House Limited | Education | 2024 |
| Acorn Plastech (UK) Limited | Manufacturing | 2005 |
| Acornleaf Limited | Extraterritorial | 1993 |
| Acquia Ltd | Information & communication | 2011 |
| Acquirz Ltd | Information & communication | 2019 |
| Acre Associates Ltd | Construction | 2012 |
| Acrefield Trustees Limited | Professional & scientific | 2025 |
| Acres Property Investment Limited | Real estate | 2024 |
| ACT Direct Limited | Construction | 2000 |
| Actio Legal Services Limited | Professional & scientific | 2010 |
| Action Events Limited | Administrative & support | 1998 |
| Action Image Productions Ltd | Information & communication | 2004 |
| Active Bits Limited | Information & communication | 2012 |
| Active Funding Ltd | Education | 2017 |
| Active Scaffolding Cheltenham Ltd | Construction | 2025 |
| Activist Team Limited | Professional & scientific | 2025 |
| Acton House (Cheltenham) Management Company Limited | Households | 1998 |
| Actual Roofing Ltd | Construction | 2025 |
| Actuator Electronic Designs Ltd | Manufacturing | 2012 |
| Acumentec Ltd | Professional & scientific | 2022 |
| Acupin Limited | Professional & scientific | 2013 |
| AD Maiora Holdings LLP | | 2023 |
| AD Meliora Holdings Limited | Real estate | 2021 |
| AD Passive Fire Protection Ltd | Construction | 2020 |
| Ad&S Ltd. | Professional & scientific | 2017 |
| Ad-Vantage Infoserve Limited | Information & communication | 1998 |
| Adam Clayton Electrical Limited | Construction | 2013 |
| Adam Finch Film Ltd | Information & communication | 2023 |
| Adam Halliwell Property Limited | Real estate | 2020 |
| Adams Coastal Cleaning Ltd | Real estate | 2021 |
| Adams Estate Agents Limited | Real estate | 2011 |
| Adams Installations Limited | Construction | 2007 |
| Adams Ricardo Limited | Professional & scientific | 2006 |
| Adaptable Solutions Partner Limited | Other services | 2011 |
| ADB Tech Ltd | Public administration | 2024 |
| Adcms Ltd | Professional & scientific | 2004 |
| ADD Electrical Ltd | Construction | 2025 |
| Addp Limited | Professional & scientific | 2024 |
| Adeo Ltd | Real estate | 2022 |
| Adept Business Finance Limited | Financial services | 2023 |
| Adept Heating Services Ltd | Construction | 2014 |
| Adept Wrapping Ltd | Wholesale & retail | 2019 |
| Adepto Capital Limited | Households | 2022 |
| Adeptus Software Limited | Information & communication | 2006 |
| Aderyn Hearing Ltd | Health & social care | 2024 |
| ADH Guppy Ltd | Real estate | 2020 |
| Adharv Ltd | Hospitality | 2025 |
| Adhd Hub Gloucestershire CIC | Administrative & support | 2022 |
| Adira Build Ltd | Construction | 2012 |
| Adirondack Projects Ltd | Transport & logistics | 2024 |
| Adiuvo Assist Limited | Real estate | 2019 |
| Adjacency Recruitment Limited | Administrative & support | 2010 |
| Adlkish Holdings Limited | Financial services | 2021 |
| ADM Accountancy Services Limited | Professional & scientific | 2009 |
| Admic Facilities Management Ltd | Wholesale & retail | 2023 |
| Admonitum Limited | Professional & scientific | 2011 |
| Adrian Green Builders Limited | Construction | 2002 |
| Adrian Peter Jones Ltd | Health & social care | 2022 |
| Adrian Sita Limited | Transport & logistics | 2022 |
| Adsinet-It Limited | Information & communication | 2026 |
| Adtibe Venture Holdings Ltd | Financial services | 2022 |
| Advance Care and Support Services Limited | Health & social care | 2018 |
| Advance Centre for Vocational and Life Skills LLP | | 2008 |
| Advanceconcept Residents Management Limited | Households | 1987 |
| Advanced Analytica Limited | Information & communication | 2013 |