| 12 Commercial Road Management Limited | Real estate | 2003 |
| 2V Studios Ltd | Information & communication | 2012 |
| 3DPGO Ltd | Wholesale & retail | 2022 |
| 4BOYS Holdings Limited | Financial services | 2024 |
| 4MINDS Ltd | Administrative & support | 2021 |
| A & S Brickwork Ltd | Construction | 2026 |
| A & W Consulting Limited | Information & communication | 2020 |
| A Drew Property Ltd | Real estate | 2024 |
| A J Jones Motors (Wales) Limited | Wholesale & retail | 2004 |
| A P Waters Building Contractors Limited | Construction | 2007 |
| A Personal Taste Ltd | Administrative & support | 2024 |
| A PIE in the Sky Cyfyngedig | Manufacturing | 2024 |
| A S Mahoney Decorators Limited | Construction | 2008 |
| A Wells & Co Holdings Ltd | Financial services | 2025 |
| A&A Property Care Limited | Construction | 2025 |
| A&B Convenience Store (Wales) Limited | Wholesale & retail | 2021 |
| A&B Tree Services Ltd | Agriculture & fishing | 2017 |
| A&Z Itani Holdings Ltd | Financial services | 2021 |
| A.C Autotrimmers Limited | Other services | 2016 |
| A.I.R Cladding Ltd | Construction | 2021 |
| A.J. Quinn Building Contractors Limited | Construction | 2001 |
| A.R.W. Limited | Transport & logistics | 2008 |
| Aaron Construction Services Ltd | Construction | 2017 |
| Abbyfield Construction Limited | Construction | 2000 |
| Abergavenny Dental Laboratories Limited | Health & social care | 2010 |
| Abergavenny Holdings Limited | Manufacturing | 2020 |
| ABM Small Business Solutions Limited | Professional & scientific | 2006 |
| Abrasion Ltd | Construction | 2025 |
| Access to Wellbeing CIC | Health & social care | 2026 |
| Ace Corp Holdings Ltd | Financial services | 2022 |
| Ace Tanning Salon Limited | Other services | 2023 |
| Ace-Cooling Ltd | Construction | 2021 |
| Active Angel's Group Ltd | Education | 2016 |
| ADB Machining Ltd | Manufacturing | 2016 |
| Adrian Gibbs Roofing Ltd | Construction | 2009 |
| Advanced Pet Food Ltd | Wholesale & retail | 2019 |
| AEL Engineering Limited | Manufacturing | 2025 |
| Aero Sense Limited | Professional & scientific | 2023 |
| Affordable Cars (South Wales) Limited | Wholesale & retail | 2005 |
| Affordable Leisure UK Ltd | Manufacturing | 2004 |
| Afon Llwyd Upvc Ltd | Construction | 2022 |
| Afon Lwyd Property Group Ltd | Construction | 2025 |
| AGA Kubish Ltd | Arts & recreation | 2024 |
| Ahimsa Holistics Ltd | Wholesale & retail | 2021 |
| AJ Firewood Limited | Manufacturing | 2014 |
| AJ Golf Online Ltd | Wholesale & retail | 2022 |
| AJ Housekeeping and Laundry Management Ltd | Administrative & support | 2026 |
| AJ Hull Investments Ltd | Real estate | 2024 |
| AJP Computing Limited | Wholesale & retail | 2024 |
| AJP Homes and Developments Limited | Real estate | 2025 |
| AJP Mobile Services Limited | Administrative & support | 2025 |
| Akad Solutions Ltd | Professional & scientific | 2020 |
| Akna Retail Ltd | Wholesale & retail | 2019 |
| Alan Counsell Sand and Stone Limited | Transport & logistics | 2001 |
| Albert Locke Ltd | Wholesale & retail | 2025 |
| Alcyoneus Consulting Limited | Professional & scientific | 2026 |
| Alderman Dockers Ltd | Wholesale & retail | 2024 |
| Alderson Jack Ltd | Wholesale & retail | 2025 |
| Alex Barry Construction & Developments Ltd | Construction | 2026 |
| Alford Brockwells Ltd | Wholesale & retail | 2025 |
| Alfred Bleaks Ltd | Wholesale & retail | 2025 |
| Alfred Layton Ltd | Wholesale & retail | 2025 |
| ALI Drew Presenting Limited | Professional & scientific | 2021 |
| Alias Creatives Ltd | Wholesale & retail | 2020 |
| ALL About Windows Limited | Construction | 2011 |
| ALL4ONE Media Ltd | Information & communication | 2014 |
| Almobarak Construction Limited | Construction | 2024 |
| ALT TEC Ltd | Other services | 2019 |
| Altair Executive Ltd | Professional & scientific | 2026 |
| Alvio Civil Engineering Ltd | Construction | 2012 |
| AMA Factory Ltd | Arts & recreation | 2026 |
| Amar Real Estate Ltd | Real estate | 2022 |
| AMC Precision Coatings Limited | Manufacturing | 2002 |
| AMC Rollers Limited | Manufacturing | 2001 |
| Amicus Property Solutions Limited | Construction | 2025 |
| Amleht Limited | Administrative & support | 2021 |
| AMS Real Estates Limited | Real estate | 2020 |
| AMY - Number One Ltd | Real estate | 2025 |
| Anchorman Testing Ltd | Professional & scientific | 2026 |
| Andre Hedges Surveying Ltd | Other services | 2022 |
| André Lewis Travel Limited | Transport & logistics | 2025 |
| Angel Holidays Limited | Administrative & support | 2007 |
| Angelwood Healing Centre Ltd | Health & social care | 2015 |
| Animal Attire Limited | Wholesale & retail | 2017 |
| ANP Services Limited | Wholesale & retail | 2022 |
| App Solute Survey Limited | Information & communication | 2015 |
| Applied Site Engineering Ltd | Professional & scientific | 2019 |
| Aqurate Engineering (Wales) Limited | Manufacturing | 2023 |
| Arcana Services Ltd | Construction | 2024 |
| Archbuild&Consultancy Services Limited | Construction | 2025 |
| Arctic Cooling Systems Ltd | Construction | 2022 |
| Arden Bowyer Ltd | Wholesale & retail | 2025 |
| Arden Orchards Ltd | Wholesale & retail | 2025 |
| Argyle Elliots Ltd | Wholesale & retail | 2025 |
| Arrail Property Management Ltd | Real estate | 2023 |
| Artisan Ciders & Ales Ltd | Wholesale & retail | 2021 |
| Arya Grocery Ltd | Wholesale & retail | 2021 |
| ASC Catering Ltd | Hospitality | 2022 |
| ASH Rail Ltd | Construction | 2018 |
| Ashdale Mews Management Company Limited | Households | 2016 |