| Access-Comms Ltd | Construction | 2020 |
| Accesshub Group Limited | Professional & scientific | 2025 |
| Accessible Motorhome Hire Ltd | Administrative & support | 2025 |
| Accountability Yorkshire Limited | Professional & scientific | 2023 |
| Accountancyplus Services Limited | Other services | 2016 |
| Accountants on Mission UK Ltd | Professional & scientific | 2019 |
| Accounting Connexions Ltd | Administrative & support | 2003 |
| Accounting Experts Ltd | Professional & scientific | 2020 |
| Accountswiz Ltd | Professional & scientific | 2014 |
| Accsafe Ltd | Professional & scientific | 2015 |
| Accsys Solutions Limited | Professional & scientific | 2015 |
| Accu Global Limited | Wholesale & retail | 2023 |
| Accurate Delivery Solutions Ltd | Transport & logistics | 2022 |
| Accusound Limited | Extraterritorial | 1990 |
| Ace Accountancy Solutions Limited | Administrative & support | 2010 |
| Ace Cabs Ltd | Transport & logistics | 2022 |
| Ace Customs Limited | Wholesale & retail | 2025 |
| Ace Engineering (Installation) Ltd | Professional & scientific | 2017 |
| Ace Love Ltd | Public administration | 2023 |
| Ace Recruitment (Yorkshire) Limited | Administrative & support | 2002 |
| Ace Visual & Sound Systems Limited | Information & communication | 1998 |
| Aceable Consultant Limited | Administrative & support | 2022 |
| ACG Sped Ltd | Transport & logistics | 2022 |
| ACH Frith Trading Limited | Other services | 2019 |
| Achilleion Travel Ltd | Administrative & support | 2021 |
| Acjoin Limited | Financial services | 2007 |
| Ackroyd Design Ltd | Information & communication | 2018 |
| Ackroyd Property Group Ltd | Real estate | 2025 |
| ACL Recycling Ltd | Water & waste | 2025 |
| ACL Surfacing Ltd | Construction | 2026 |
| ACM Mckee Utilities Ltd | Construction | 2022 |
| ACM Performance Ltd | Administrative & support | 2023 |
| Acmac (Worksop) Limited | Other services | 2025 |
| Acmac Martial Arts Limited | Professional & scientific | 2020 |
| Acmac(Rossington) Limited | Other services | 2025 |
| Acme Transport Services Ltd | Transport & logistics | 2022 |
| Acorn Designer Driveways Limited | Construction | 2021 |
| Acorn IT Ltd | Information & communication | 2025 |
| Acorn Landscaping & Building Ltd | Administrative & support | 2026 |
| Acorn Timber Engineering Ltd | Construction | 2009 |
| Acorn Timber Solutions Ltd | Manufacturing | 2015 |
| ACP Courier Ltd | Transport & logistics | 2025 |
| ACP Yorkshire Consultancy Limited | Professional & scientific | 2026 |
| Acquisto Limited | Wholesale & retail | 2015 |
| ACR Estate Agents Ltd | Real estate | 2024 |
| ACR Projects Ltd | Real estate | 2025 |
| ACR91 Ltd | Construction | 2023 |
| Acris Software Ltd | Information & communication | 2022 |
| Across Expert Limited | Professional & scientific | 2017 |
| ACS Hosting Servicos Ltd | Information & communication | 2020 |
| ACS Transport&Logistics Ltd | Wholesale & retail | 2019 |
| Acterial PVT Ltd | Health & social care | 2018 |
| Actiblast Ltd | Professional & scientific | 2025 |
| Action Learning Centre ALC Limited | Professional & scientific | 2015 |
| Action Meats Limited | Wholesale & retail | 1993 |
| Action Partners Corporation | Administrative & support | 1907 |
| Activ First Limited | Other services | 2009 |
| Active - Passive Fire Protection Limited | Construction | 2024 |
| Active Always Limited | Health & social care | 2015 |
| Active Care 4U Limited | Health & social care | 2016 |
| Active Care Homes Limited | Health & social care | 2005 |
| Active Care Housing Limited | Real estate | 2020 |
| Active Communities CIC | Education | 2023 |
| Active Independence | Other services | 2012 |
| Active Kitchen Ltd | Hospitality | 2026 |
| Active Lives Active Communities CIC | Health & social care | 2018 |
| Active PAT Testing UK Ltd | Professional & scientific | 2025 |
| Active Pro Ltd | Other services | 2013 |
| Acumen Legal Ltd | Professional & scientific | 2024 |
| Acupuncture on Tour Ltd | Agriculture & fishing | 2020 |
| Acura Travel Ltd | Transport & logistics | 2024 |
| AD Lounge Bar Ltd | Hospitality | 2025 |
| AD Solutions Doncaster Ltd | Professional & scientific | 2021 |
| AD Vision Value Limited | Wholesale & retail | 2025 |
| ADA Carriage Ltd | Transport & logistics | 2020 |
| ADA Good Food Limited | Hospitality | 2024 |
| ADA J Shopfitting Ltd | Construction | 2026 |
| Adact Primary Authority Partnership Ltd | Administrative & support | 2018 |
| Adakify Limited | Information & communication | 2022 |
| Adal Electrical Limited | Energy | 2026 |
| Adal Homes Limited | Real estate | 2024 |
| Adal Plumbing & Heating Limited | Construction | 2022 |
| Adal Property Investments Limited | Real estate | 2023 |
| Adam Aveling Coaching Limited | Arts & recreation | 2021 |
| Adam Brothers Ltd | Construction | 2023 |
| Adam Clarke Ltd | Financial services | 2014 |
| Adam Feast Aesthetics Limited | Other services | 2024 |
| Adam Fritchley TM Ltd | Construction | 2025 |
| Adam G. Cars Limited | Wholesale & retail | 2024 |
| Adam Packaging Solutions Ltd | Administrative & support | 2026 |
| Adam Sure Diesel Ltd | Wholesale & retail | 2025 |
| Adam.Ali Transport Ltd | Transport & logistics | 2014 |
| Adams (Fairfield Garages) Limited | Real estate | 1938 |
| Adams Residential Lettings Ltd | Hospitality | 2024 |
| ADAPT4DESIGN Limited | Construction | 2014 |
| Adapta Resources Ltd | Wholesale & retail | 2024 |
| Adapted Motorhome Hire Ltd | Administrative & support | 2025 |
| Adaptive Device Solutions Ltd | Public administration | 2019 |
| Adben Design Ltd | Information & communication | 2017 |
| Adcomp Groep Limited | Administrative & support | 1992 |