| A & H Rendering Ltd | Construction | 2017 |
| A & J Builders ( Mountain ASH) Limited | Administrative & support | 2017 |
| A & J Flooring Services Ltd | Construction | 2019 |
| A J Marsh Services Limited | Construction | 2019 |
| A&G Electrical Contractors Ltd | Construction | 2018 |
| Abercynon Rugby Football Club | Other services | 2007 |
| Abergissey Property Ltd | Real estate | 2024 |
| ABH Rendering Ltd | Construction | 2025 |
| Abkazefba Limited | Wholesale & retail | 2025 |
| Able Home Investments Ltd | Real estate | 2019 |
| Absolute Ecommerce Ltd | Wholesale & retail | 2025 |
| Absolute Futures Trading Ltd | Financial services | 2025 |
| Absolute Innovations Ltd | Financial services | 2025 |
| Absolute Rail Consultancy Ltd | Professional & scientific | 2025 |
| Absolute Vans Ltd | Wholesale & retail | 2024 |
| Access 2 Aesthetics Cardiff Ltd | Education | 2023 |
| Access 2 Aesthetics Ltd | Health & social care | 2021 |
| Accessible Caring Transport | Transport & logistics | 1992 |
| Ace Roller Shutters Ltd | Manufacturing | 2025 |
| Acuma Properties Ltd | Real estate | 2019 |
| Adore Lounge Ltd | Hospitality | 2024 |
| Adss Cymru (Wales) Ltd | Other services | 2018 |
| Advance Netball Limited | Education | 2025 |
| Aeroresponse Ltd | Manufacturing | 2002 |
| Air Jointing Limited | Construction | 2026 |
| Aish & ABI Ltd | Wholesale & retail | 2021 |
| AJR Electrical Services & Contractors Limited | Construction | 2022 |
| Alexas Mini Market Ltd | Wholesale & retail | 2025 |
| ALL Plant Operator and Repair Services Limited | Manufacturing | 2021 |
| Aloha Telecommunications Ltd | Information & communication | 2010 |
| Alpine Build Developments Ltd | Construction | 2022 |
| Alpine Build UK Ltd | Administrative & support | 2017 |
| Amira’S Falafel Ltd | Hospitality | 2025 |
| Anavrin Yoga Academy Ltd | Education | 2025 |
| Anian Capital Limited | Financial services | 2025 |
| Anian Holdings Limited | Financial services | 2025 |
| Anian Investments Limited | Financial services | 2025 |
| Anibla Properties Limited | Real estate | 2019 |
| ANM Electronics Limited | Manufacturing | 2016 |
| ANM Logistics Limited | Transport & logistics | 2012 |
| ANM Opto Limited | Manufacturing | 2010 |
| Anything Property Maintenance Ltd | Real estate | 2025 |
| AP Civils Ltd | Construction | 2018 |
| Aqms Consulting Ltd | Professional & scientific | 2016 |
| ARC Training Co (Arco) Ltd | Education | 2011 |
| Arco (ARC) Training Ltd | Administrative & support | 2025 |
| Arglwydd Ltd | Wholesale & retail | 2026 |
| Arien Lifestyle Limited | Wholesale & retail | 2018 |
| ARK Motorsport Ltd | Arts & recreation | 2024 |
| Arquus Consulting Ltd | Professional & scientific | 2021 |
| Ashden Properties Ltd | Real estate | 2021 |
| Ashfield Flood Risk Solutions Limited | Professional & scientific | 2015 |
| Ashfield Risk Transfer Solutions Limited | Financial services | 2016 |
| Ashfield Solutions Limited | Administrative & support | 2006 |
| Ashfield Solutions Group Limited | Professional & scientific | 2015 |
| ASK & Partners Legal Solutions Ltd | Professional & scientific | 2024 |
| ASN General Store Ltd | Wholesale & retail | 2018 |
| ATW Groundworks and Civil Engineering Limited | Construction | 2014 |
| B&J Friary Chip Shop Ltd | Hospitality | 2024 |
| B.L.W. Butts Limited | Professional & scientific | 2025 |
| Babis Homes Limited | Construction | 2014 |
| Bailams Insolvency Practitioners Ltd | Professional & scientific | 2009 |
| Baileys Pubs Limited | Hospitality | 2019 |
| Barlam Ltd. | Construction | 2015 |
| Barnard Drylining & SFS Specialist Ltd | Construction | 2026 |
| BAS Plastering Ltd | Construction | 2023 |
| BB Carpets and Flooring Ltd | Wholesale & retail | 2010 |
| Beanie Rail Ltd. | Construction | 2016 |
| Bennett Motor Cars Ltd | Wholesale & retail | 2025 |
| Bennett's Accountancy Services Ltd | Professional & scientific | 2024 |
| Bgun of Africa International Limited | Administrative & support | 2024 |
| Bismillah Zara Ltd | Hospitality | 2019 |
| Blue Light Services Group Holdings Limited | Manufacturing | 2024 |
| Botransport Ltd | Transport & logistics | 2017 |
| Brickzen Constructions Ltd | Construction | 2026 |
| Brigadoon (Ffos) Ltd | Real estate | 2023 |
| Brightboard AI Ltd | Information & communication | 2025 |
| Brookmex Limited | Real estate | 2001 |
| Bryncynon Community Revival Strategy Limited | Hospitality | 1996 |
| Build-Tec Contractors Limited | Construction | 2008 |
| Bush & Griffiths Limited | Wholesale & retail | 2003 |
| Bush Accessible Transport Services Limited | Transport & logistics | 2018 |
| C&L Property Developers Ltd | Real estate | 2023 |
| C&L Rendering Ltd | Construction | 2021 |
| C&M Jones Groundworks Limited | Construction | 2020 |
| Calum Biggs Ltd | Financial services | 2023 |
| Cambrian Community Ltd | Hospitality | 2018 |
| Capan's House Ltd | Hospitality | 2025 |
| Cardiff Road Garage Limited | Wholesale & retail | 2012 |
| Celebrating Cultures Limited | Arts & recreation | 2000 |
| Cheryl's Fruit & VEG Limited | Wholesale & retail | 2009 |
| Choiceitsupportsolution Ltd | Information & communication | 2026 |
| Christopher Davies Photography Ltd | Professional & scientific | 2025 |
| Christopher Smale Limited | Construction | 2016 |
| Circle Cardiovascular Imaging UK Ltd | Information & communication | 2015 |
| Circuita Ltd | Wholesale & retail | 2025 |
| Citizens Advice Rhondda Cynon TAF Ltd. | Information & communication | 1999 |
| City Intelligence Ltd | Information & communication | 2025 |
| CJ Rendering Ltd | Construction | 2021 |
| Claudio Cernat Ltd | Hospitality | 2015 |