| Ace Truck Drive Ltd | Transport & logistics | 2022 |
| ACE123 Limited | Professional & scientific | 2023 |
| Aceforce Limited | Hospitality | 1999 |
| Acemax Estates Ltd | Manufacturing | 1997 |
| Acer Property Consultants Ltd | Real estate | 2016 |
| Acero Designs Limited | Construction | 2023 |
| Acero Structures Limited | Construction | 2023 |
| Aces Hodl Ltd | Information & communication | 2024 |
| Acevan Create Ltd | Wholesale & retail | 2025 |
| Acevan Events Ltd | Other services | 2025 |
| ACG Management Limited | Real estate | 2019 |
| ACG Marketing Team Ltd | Other services | 2024 |
| Acgc Property Limited | Real estate | 2017 |
| Achieveit (Salop) Limited | Professional & scientific | 2001 |
| Achievers Tutoring Services Limited | Education | 2015 |
| Achilles Building Services Limited | Real estate | 1993 |
| Achis Property Services Ltd | Construction | 2013 |
| Aclw Transport Ltd | Transport & logistics | 2022 |
| ACM Asbestos Consulting Ltd | Professional & scientific | 2019 |
| ACM Caretaking Ltd | Administrative & support | 2025 |
| ACM Flooring Installers Ltd | Construction | 2026 |
| ACM Heating & Plumbing Limited | Construction | 2018 |
| ACM Imaging Ltd | Health & social care | 2022 |
| ACM Plumbing & Heating Ltd | Construction | 2023 |
| ACM Property Group Ltd | Real estate | 2025 |
| Acme Supply Co Ltd | Administrative & support | 2018 |
| ACME247 Consult Limited | Administrative & support | 2017 |
| Acor Building & Property Solutions Ltd | Construction | 2014 |
| Acorn & Oak Limited | Hospitality | 2005 |
| Acorn Children Care Ltd | Health & social care | 2026 |
| Acorn Commodities Broking and Trading Limited | Wholesale & retail | 2020 |
| Acorn Commodities Limited | Wholesale & retail | 2013 |
| Acorn Consultancy Solutions Limited | Professional & scientific | 2018 |
| Acorn Contract Services Ltd | Arts & recreation | 1998 |
| Acorn Developments (NW) Ltd | Financial services | 2025 |
| Acorn Group Services Limited | Professional & scientific | 2007 |
| Acorn Holdco 2 Limited | Financial services | 2017 |
| Acorn Insurance and Financial Services Limited | Financial services | 1982 |
| Acorn Kitchens & Bedrooms Formby Limited | Construction | 2025 |
| Acorn Pictures Limited | Information & communication | 2022 |
| Acorn Pictures Properties Company Limited | Real estate | 2023 |
| Acorn Recovery Limited | Wholesale & retail | 2025 |
| Acorn Venture Trading Co. Ltd | Other services | 2005 |
| Acoustic Machines Limited | Manufacturing | 2019 |
| Acoustic Percussion Limited | Wholesale & retail | 2011 |
| ACP Healthcare Services Ltd | Health & social care | 2022 |
| ACP Tooling Limited | Professional & scientific | 2025 |
| Acquah Logistics Ltd | Transport & logistics | 2025 |
| Acquipeak Group Holdings Limited | Financial services | 2019 |
| Acquipeak Project Holdings Limited | Financial services | 2023 |
| Acquipeak Property Holdings Limited | Financial services | 2019 |
| Acquire Property Ltd | Real estate | 2025 |
| Acquired Management Ltd | Households | 2026 |
| Acquiro Group Limited | Professional & scientific | 2025 |
| Acquisition Advisors Ltd | Professional & scientific | 2019 |
| Acquisition Consultants Ltd | Professional & scientific | 2012 |
| ACR Recovery Services Ltd | Wholesale & retail | 2025 |
| Acre Development Consulting Limited | Professional & scientific | 2015 |
| Acre Street Properties Ltd | Hospitality | 2022 |
| Acreative AI Ltd | Wholesale & retail | 2025 |
| Acresfield Limited | Construction | 2005 |
| Acrestone Developments Ltd | Real estate | 2023 |
| Acrestone Properties Ltd | Real estate | 2004 |
| Acronym Community Empowerment (Ace) | Professional & scientific | 2015 |
| Acropolis Restaurant Ltd | Hospitality | 2018 |
| ACS (NW) Ltd | Other services | 2016 |
| ACS Healthsolutions Limited | Health & social care | 2012 |
| ACS Holdings NW Ltd | Financial services | 2025 |
| ACS Investment Group Ltd | Real estate | 2025 |
| ACT for Action Community Interest Company | Administrative & support | 2018 |
| ACT Formwork Ltd | Construction | 2025 |
| ACT NOW Energy Ltd | Professional & scientific | 2025 |
| ACT Property Investments Ltd | Real estate | 2018 |
| Acta Edge Limited | Information & communication | 2026 |
| Actexact Group Limited | Real estate | 2024 |
| Actexact Limited | Real estate | 2019 |
| Acting Angels C.I.C. | Education | 2015 |
| Action Pest Control Facilities Ltd | Administrative & support | 2013 |
| Action Props Ltd | Information & communication | 2024 |
| Action Vehicle Services Ltd | Administrative & support | 2024 |
| ACTION8STUNTS Limited | Arts & recreation | 2025 |
| Actionjackson Limited | Hospitality | 2025 |
| Actions NOW Ltd | Administrative & support | 2021 |
| Actions on Consultancy Ltd | Administrative & support | 2020 |
| ACTIV8 Protection Ltd | Administrative & support | 2025 |
| Activate Body & Mind Community Activities C.I.C. | Other services | 2022 |
| Activate Digital Limited | Professional & scientific | 2017 |
| Active 8 Liverpool Limited | Administrative & support | 2007 |
| Active 8 Support Services Limited | Public administration | 2006 |
| Active Apartments Limited | Real estate | 2019 |
| Active Careers Ltd | Administrative & support | 2017 |
| Active Community Enterprise (A.C.E.) Community Interest Company | Health & social care | 2009 |
| Active Elite Limited | Manufacturing | 2025 |
| Active Flooring Solutions Limited | Construction | 2011 |
| Active International Business Management Limited | Extraterritorial | 2015 |
| Active Ireland Ltd | Administrative & support | 2009 |
| Active Liverpool C.I.C. | Construction | 2020 |
| Active Minds Limited | Information & communication | 2009 |
| Active Minds Social Club Ltd | Health & social care | 2026 |
| Active Public Relations Limited | Professional & scientific | 1993 |