| Accepty Technology Ltd | Information & communication | 2018 |
| Access International Consulting Limited | Professional & scientific | 2002 |
| Access SEN Education and Consultancy Ltd | Education | 2024 |
| Accipiter Publishing Ltd | Information & communication | 2021 |
| Accommodation Links Limited | Real estate | 2008 |
| Accord Care Homes Ltd | Health & social care | 2022 |
| Accountancy by Birch Consulting Limited | Professional & scientific | 2015 |
| Accounting for Safety Limited | Professional & scientific | 2004 |
| Accounts and Tax Centre Ltd | Professional & scientific | 2001 |
| Accura Construct Ltd | Construction | 2024 |
| Accurate Properties Ltd | Real estate | 2025 |
| Accuris Limited | Hospitality | 2016 |
| Accusurv Limited | Professional & scientific | 2023 |
| Ace Academy Limited | Education | 2025 |
| Ace Design and Print Limited | Manufacturing | 2016 |
| Ace Enterprise MCR Limited | Administrative & support | 2024 |
| Ace Print Services (Stockport) Limited | Manufacturing | 2022 |
| Ace Stuff Ltd | Wholesale & retail | 2025 |
| Ace Trading Partners Ltd | Wholesale & retail | 2025 |
| Acer Learning Ltd | Education | 2024 |
| ACH Property Ltd | Real estate | 2019 |
| Achadwicks PM Ltd | Professional & scientific | 2024 |
| Achefabroad Tours Ltd | Administrative & support | 2024 |
| ACK Lane Limited | Professional & scientific | 2012 |
| Acknowledge Ltd | Other services | 2026 |
| ACL DRY Goods Wholesale Ltd | Wholesale & retail | 2025 |
| Acme Robots Limited | Information & communication | 2023 |
| Acoffer Limited | Financial services | 2023 |
| Acomb Removals Ltd | Transport & logistics | 2013 |
| Acorn Business Centres (Stockport) Limited | Real estate | 1989 |
| Acorn Civils Ltd | Construction | 2024 |
| Acourseras Beauty Institut Ltd | Education | 2025 |
| Acoustic & Engineering Consultants Holding Limited | Professional & scientific | 2019 |
| Acoustic and Engineering Consultants Limited | Professional & scientific | 1992 |
| Acoustico UK Limited | Construction | 2018 |
| ACP Facilities Management Limited | Administrative & support | 2025 |
| Acquest Ltd | Hospitality | 2016 |
| Acquitaine Limited | Manufacturing | 2005 |
| Acquos Ltd | Administrative & support | 2008 |
| ACR PVC and Joinery Limited | Construction | 2023 |
| Acro Engineering Ltd | Manufacturing | 2025 |
| ACS (North) Ltd | Health & social care | 2018 |
| ACS Construction Group Ltd. | Construction | 1997 |
| ACS Group Holdings Limited | Financial services | 2008 |
| ACS Plant Limited | Extraterritorial | 2008 |
| ACS Support Limited | Administrative & support | 2023 |
| ACT & Impact Ltd | Arts & recreation | 2025 |
| ACT Energy Consulting Limited | Professional & scientific | 2020 |
| ACT Fast Roofing Ltd | Construction | 2025 |
| Action Properties (North West) Limited | Professional & scientific | 2008 |
| Actionwell Limited | Hospitality | 1996 |
| Activate Tuition Inc. Ltd. | Education | 2020 |
| Active Builders Limited | Administrative & support | 2008 |
| Active Communities Experiences Ltd | Arts & recreation | 2019 |
| Active House Scandinavia Ltd | Administrative & support | 2009 |
| Active Installs Ltd | Construction | 2019 |
| Active Kids Education Limited | Education | 2017 |
| Active Resource (UK) Limited | Administrative & support | 1999 |
| Active Security Systems Limited | Construction | 2003 |
| Active Synergie Consulting Ltd | Professional & scientific | 2006 |
| Activetots Limited | Arts & recreation | 2012 |
| Acto Property Limited | Real estate | 2025 |
| Acton Signature Properties Ltd | Real estate | 2024 |
| Actree Accountancy Ltd | Professional & scientific | 2011 |
| Acuma Solutions Limited | Information & communication | 2000 |
| Acumen Field Limited | Professional & scientific | 2016 |
| Acwin Commercial Ltd | Wholesale & retail | 2023 |
| Acwin Enterprise Ltd | Wholesale & retail | 2021 |
| Acwin Investments Ltd | Wholesale & retail | 2024 |
| Acwin Retail Ltd | Wholesale & retail | 2021 |
| Acwin Ventures Ltd | Wholesale & retail | 2023 |
| Aczone Limited | Administrative & support | 2025 |
| AD Aerospace Limited | Administrative & support | 1995 |
| AD Astra Productions Limited | Administrative & support | 2012 |
| AD Autos Ltd | Wholesale & retail | 2017 |
| AD Claritatem Limited | Professional & scientific | 2018 |
| AD HOC Group Limited | Information & communication | 2016 |
| AD HOC Occupational Health Limited | Health & social care | 2014 |
| Adam Griffiths Holdings Ltd | Financial services | 2022 |
| Adam Hammour Limited | Arts & recreation | 2017 |
| Adam James Poynton Ltd | Other services | 2012 |
| Adam Mustafa Engineering Services Ltd | Professional & scientific | 2019 |
| Adam Potts Ltd | Real estate | 2020 |
| Adam Wojnar Property Invest Limited | Real estate | 2023 |
| Adamas Hardware Limited | Administrative & support | 2014 |
| Adampol Ltd | Real estate | 2026 |
| Adampol Properties Limited | Construction | 2025 |
| Adana Construction Ltd | Construction | 2000 |
| Adaptacare Limited | Construction | 1997 |
| Adaptation Building Services Ltd | Construction | 2011 |
| Adaptive Health Ltd | Wholesale & retail | 2023 |
| Adaptive Path Community CIC | Health & social care | 2026 |
| Adaptsoft Ltd | Information & communication | 2010 |
| Adaptwear Solutions Limited | Manufacturing | 2024 |
| Adbr Limited | Professional & scientific | 2014 |
| ADD Properties Global Ltd | Real estate | 2021 |
| Addedpixels Limited | Information & communication | 2025 |
| Addworx Limited | Professional & scientific | 2022 |
| Adele James Pet Services Ltd | Agriculture & fishing | 2022 |
| Adelina Fish & Chips Limited | Hospitality | 2025 |