| AB Electrical & Renovations Ltd | Administrative & support | 2024 |
| AB Initio Designs Ltd | Professional & scientific | 2021 |
| AB Offshore Lifting Services Limited | Administrative & support | 2015 |
| AB Petrophys Ltd | Mining & quarrying | 2020 |
| AB Process Support Ltd | Professional & scientific | 2017 |
| AB Property Solutions (NW) Ltd | Real estate | 2026 |
| AB Stunts Limited | Other services | 2017 |
| Abandoned Coffeeshop Software Ltd. | Administrative & support | 2014 |
| ABB Cable Management Products Limited | Manufacturing | 1960 |
| ABB E-Mobility UK Limited | Manufacturing | 2021 |
| ABB Holdings Limited | Professional & scientific | 1994 |
| ABB Installation Products Limited | Manufacturing | 1969 |
| ABB Limited | Manufacturing | 1999 |
| ABB Robotics UK Limited | Manufacturing | 2025 |
| Abba Cars (Warrington) Limited | Transport & logistics | 2002 |
| Abbey Leisure Burtonwood Limited | Arts & recreation | 2008 |
| Abbey Logistics Group Limited | Transport & logistics | 1990 |
| Abbey Pack Eggs 2018 Limited | Wholesale & retail | 2018 |
| Abbey& SON Limited | Health & social care | 2016 |
| Abbeystore Limited | Education | 2002 |
| Abbots Park Management Company Limited | Real estate | 2003 |
| Abbott Wade Ltd | Construction | 2010 |
| Abbs Almani Engineering Limited | Administrative & support | 2016 |
| ABC 123 Day Nursery Limited | Education | 2009 |
| ABC at Leeds FC Ltd | Administrative & support | 2009 |
| ABC Bureau Ltd | Professional & scientific | 2016 |
| ABC Leisure (Warrington) Limited | Arts & recreation | 2015 |
| Abeco Limited | Professional & scientific | 2017 |
| Abell Testing Solutions Ltd | Administrative & support | 2026 |
| ABF Operations Limited | Financial services | 2022 |
| ABG Network NW Logistics Ltd | Transport & logistics | 2021 |
| ABH Properties Ltd | Households | 2025 |
| Abhinav Technologies Limited | Administrative & support | 2012 |
| Abigail Alexandria Academy Limited | Other services | 2023 |
| Abigail Alexandria Limited | Other services | 2016 |
| Abigail Alexandria the Salon Limited | Other services | 2024 |
| Ability Housing Community Interest Company | Real estate | 2024 |
| Abily Consultancy Ltd | Information & communication | 2024 |
| Abisuk Ltd | Construction | 2024 |
| Ablah Consulting Limited | Other services | 2018 |
| Ablbt Limited | Administrative & support | 2023 |
| Able Creative Ltd | Professional & scientific | 2016 |
| Able Modular Technologies Limited | Manufacturing | 2014 |
| Able Quality Services Limited | Administrative & support | 2013 |
| Ablelectrical Services Ltd | Construction | 2020 |
| Ablesky Limited | Wholesale & retail | 2002 |
| About Time Button Limited | Financial services | 2023 |
| Above & Beyond Travel by Joanne Ltd | Administrative & support | 2024 |
| ABP Advisory Services Limited | Professional & scientific | 2026 |
| ABP Distribution Limited | Transport & logistics | 2011 |
| ABP Solutions Limited | Professional & scientific | 2016 |
| Abramatic Advisory Ltd | Administrative & support | 2026 |
| Abry Consulting Limited | Professional & scientific | 2014 |
| Abry Homes Limited | Real estate | 2024 |
| ABS Consultancy Services Limited | Financial services | 2006 |
| ABS Consulting Ltd. | Professional & scientific | 1987 |
| ABS Group Ltd. | Professional & scientific | 1990 |
| ABS Management Limited | Real estate | 2025 |
| ABS QE Assurance Services (UK) Ltd | Professional & scientific | 2021 |
| Absc Solutions Ltd | Administrative & support | 2012 |
| Absolute BI Solutions Ltd. | Information & communication | 2011 |
| Absolute Contract Control Limited | Administrative & support | 2021 |
| Absolute Data Management Limited | Information & communication | 2017 |
| Absolute Kitchens (NW) Ltd | Wholesale & retail | 2012 |
| Absolute Property Support Ltd | Real estate | 2024 |
| Abyr Construction Limited | Construction | 2026 |
| AC Equine Ltd | Other services | 2018 |
| AC Pro Engineering Ltd | Administrative & support | 2016 |
| AC Procurement Ltd | Administrative & support | 2014 |
| AC Property Group Ltd | Real estate | 2018 |
| AC Squared Developments Ltd | Professional & scientific | 2022 |
| AC Water Limited | Administrative & support | 2010 |
| Ac&E Limited | Information & communication | 2007 |
| ACA Academy Ltd | Education | 2025 |
| Acaba Consultancy Services Ltd | Other services | 2018 |
| Academy Lashes Ltd | Other services | 2017 |
| Academy Lifts Limited | Manufacturing | 2002 |
| Acadian Consulting Ltd | Information & communication | 2012 |
| Acai Heaven UK Ltd | Hospitality | 2026 |
| Acai Heaven Warrington Ltd | Hospitality | 2025 |
| ACB Planning Services Ltd | Administrative & support | 2024 |
| Accede Consulting Ltd | Professional & scientific | 2014 |
| Accelerated Digital Delivery Ltd | Education | 2018 |
| Accelerated Weathering Laboratory Limited | Professional & scientific | 2005 |
| Accell Digital Limited | Professional & scientific | 2021 |
| Accentium Ltd | Professional & scientific | 2014 |
| Access & Security Ltd | Wholesale & retail | 2021 |
| Access Business Solutions Limited | Professional & scientific | 2011 |
| Access Freedom Experiences CIC | Professional & scientific | 2024 |
| Access Freedom Ltd | Manufacturing | 2021 |
| Access-Able (UK) Limited | Construction | 2013 |
| Accfin Services Ltd | Professional & scientific | 2022 |
| Accident Credit Group Ltd | Administrative & support | 2010 |
| Accident Credit Limited | Extraterritorial | 2010 |
| Acclaimed Accommodation Ltd | Hospitality | 2022 |
| Acclaimed Living UK Ltd | Real estate | 2020 |
| Accolade Social Care CIC | Administrative & support | 2021 |
| Accountancy Summit Limited | Professional & scientific | 2008 |
| Accountancy Value Limited | Professional & scientific | 2016 |
| Accounting Evolution Ltd | Professional & scientific | 2024 |