| Abbeydale Training Limited | Education | 1999 |
| Abbsi Ltd | Wholesale & retail | 2025 |
| ABC Auctions Ltd | Wholesale & retail | 2020 |
| ABC Mechanics Ltd | Professional & scientific | 2026 |
| ABC Motors Limited | Wholesale & retail | 2025 |
| Abcom Consulting Ltd | Professional & scientific | 2019 |
| Abell Associates Ltd | Transport & logistics | 2025 |
| Abels Maintenance Ltd | Construction | 2023 |
| Abhi Products Ltd | Manufacturing | 2025 |
| Able and Creative Ltd | Professional & scientific | 2019 |
| Ablm Limited | Information & communication | 2023 |
| Abrig Properties Limited | Real estate | 2023 |
| Absolute Energy Ltd | Professional & scientific | 2021 |
| Absolute Water Compliance Limited | Other services | 2022 |
| Absolute Web Design Limited | Information & communication | 2002 |
| Abstract Building and Maintenance Ltd | Construction | 2020 |
| Absurdity Games Ltd | Information & communication | 2024 |
| Abubakersiddiqu Ltd | Wholesale & retail | 2025 |
| ABW Joinery Building Ltd | Construction | 2018 |
| Abydoz Limited | Construction | 2021 |
| Abytrans Personell Limited | Transport & logistics | 2019 |
| AC Personal Training Ltd | Health & social care | 2025 |
| ACA Healthcare Ltd | Professional & scientific | 2025 |
| Academy of Friends CIC | Manufacturing | 2024 |
| ACB Lettings Ltd | Real estate | 2024 |
| ACB Utilities Ltd | Construction | 2018 |
| Accede Support Limited | Health & social care | 2022 |
| Access Install Limited | Energy | 2015 |
| Access Operators (AXS OPS) Ltd | Administrative & support | 2019 |
| Accessidea Limited | Real estate | 2000 |
| Accounting 4 Limited | Professional & scientific | 2014 |
| Ace (South Yorkshire) Ltd | Construction | 2011 |
| Ace Joinery Ltd. | Construction | 2015 |
| Acgp Enterprises Ltd | Wholesale & retail | 2025 |
| ACM Trades International Limited | Wholesale & retail | 2023 |
| Acorn Brewery of Barnsley Limited | Manufacturing | 2003 |
| Acorn Fish and Chips Ltd | Hospitality | 2019 |
| Acquisition IT Limited | Administrative & support | 2016 |
| ACR Commercial & Finance Ltd | Administrative & support | 2017 |
| ACT Rail Ltd | Manufacturing | 2026 |
| ACT Scaffolding Services Ltd | Construction | 2015 |
| Action Arts Limited | Administrative & support | 2006 |
| Action Mann Limited | Information & communication | 2017 |
| Action Plastics Ltd | Manufacturing | 2018 |
| Active Barnsley Ltd | Arts & recreation | 2006 |
| Active Consulting Limited | Professional & scientific | 2000 |
| Active Marketing Solutions UK Ltd | Professional & scientific | 2019 |
| Active Provision CIC | Education | 2026 |
| Active Training & Testing Solutions Limited | Professional & scientific | 2012 |
| Acton Chase Associate Limited | Professional & scientific | 2017 |
| ACU Commercial Limited | Administrative & support | 2017 |
| Acura Energy Controls Ltd | Construction | 2012 |
| Acura Network Installations Ltd | Construction | 2024 |
| ACW Utility Solutions Limited | Construction | 2018 |
| AD Astra Barnsley CIC | Health & social care | 2013 |
| AD Power Solutions Limited | Construction | 2025 |
| AD Steel Fixers Ltd | Construction | 2024 |
| ADA & Iris Ltd | Other services | 2026 |
| ADA ELA Ltd | Hospitality | 2024 |
| ADA IT Ltd | Information & communication | 2019 |
| Adam D Trans Ltd | Transport & logistics | 2017 |
| Adam Newman Holdings Limited | Financial services | 2024 |
| Adam Whittaker & Sons Limited | Wholesale & retail | 2018 |
| Adams Builders Limited | Construction | 2026 |
| Adams UK Properties Ltd | Real estate | 2023 |
| Adan Leisure Ltd | Hospitality | 2019 |
| Adaptafit Property Solutions Ltd | Construction | 2026 |
| ADD Worth Properties Limited | Real estate | 2024 |
| Addan Properties Limited | Real estate | 2017 |
| Addicted Limited | Other services | 2013 |
| Addiction Rehab Ltd | Health & social care | 2023 |
| Adeca Ltd | Professional & scientific | 2013 |
| Adelphi Studio Ltd | Information & communication | 2013 |
| Adelphi Translations Limited | Administrative & support | 2009 |
| Adknow Limited | Professional & scientific | 2025 |
| ADM Chmielewski Ltd | Transport & logistics | 2020 |
| ADN Support & Development Limited | Professional & scientific | 2023 |
| Adomast Manufacturing Limited | Manufacturing | 2011 |
| Adore Aesthetics and Medispa Limited | Health & social care | 2025 |
| ADR Transport Solutions Limited | Transport & logistics | 2023 |
| Adrian Allen Limited | Other services | 2014 |
| Adrian Avram Limited | Transport & logistics | 2018 |
| ADS Private Ltd | Wholesale & retail | 2023 |
| Adskill Ltd | Education | 2004 |
| Advance Industrial Pipework Ltd | Manufacturing | 2017 |
| Advanced Acquisitions Ltd | Real estate | 2023 |
| Advanced Assessment & Solutions Limited | Health & social care | 2021 |
| Advanced Emergency Vehicles Limited | Manufacturing | 2024 |
| Advanced Excavation Limited | Construction | 2015 |
| Advanced Turf Technology Ltd | Administrative & support | 2016 |
| Advntm Limited | Other services | 2019 |
| ADY Shorthouse Transport Limited | Transport & logistics | 2003 |
| AEC Live Ltd | Administrative & support | 2011 |
| AEJ Properties Ltd | Real estate | 2025 |
| AEP Consulting Limited | Professional & scientific | 2023 |
| AER (Development) Ltd | Real estate | 2020 |
| Aerials & Cctv by KAL Ltd | Construction | 2023 |
| AES Barnsley Ltd | Construction | 2025 |
| AES South Yorkshire Ltd | Professional & scientific | 2019 |
| Aesthetic Cleaning and Maintenance Services Limited | Administrative & support | 2020 |