| 145 NP20 Ltd | Other services | 2023 |
| 42 Foods Ltd | Hospitality | 2026 |
| A & D Reynolds Ltd | Wholesale & retail | 2008 |
| A & T Bathrooms Ltd | Construction | 2023 |
| A J Upholstery Limited | Other services | 2013 |
| A M Business Consultants Ltd | Professional & scientific | 2020 |
| A&B Convenience Store (Newport) Ltd | Real estate | 2025 |
| A&S Wood Products Limited | Manufacturing | 2018 |
| A.T.E Prime Services Ltd | Wholesale & retail | 2025 |
| Aarons Painting Ltd | Construction | 2025 |
| AB Clearances Ltd | Water & waste | 2013 |
| AB Installations & Property Maintenance Ltd | Construction | 2018 |
| Abbey Glass (Cardiff) Limited | Manufacturing | 1992 |
| ABC Virtual Assistants Limited | Administrative & support | 2020 |
| Acorn Consultancy Limited | Professional & scientific | 2017 |
| Acorn Property (South Wales) Limited | Real estate | 2012 |
| Acorn Property Limited | Real estate | 2016 |
| Acorn Property Rentals (South Wales) Limited | Real estate | 2013 |
| ACP Data Solutions Ltd | Professional & scientific | 2026 |
| ADS Electrical Limited | Construction | 2016 |
| AEG Housing and Lettings Limited | Real estate | 2026 |
| AG Tempered Limited | Construction | 2017 |
| AH Finishing and Developments Ltd | Construction | 2026 |
| AJ & Sons Holdings Limited | Real estate | 2026 |
| AJ Commissioning Ltd | Construction | 2024 |
| AJM Fire Prevention Ltd | Professional & scientific | 2017 |
| Akash Jewellery Ltd | Wholesale & retail | 2018 |
| Albert & Laura Limited | Real estate | 2024 |
| ALH Management Consultants Limited | Real estate | 2008 |
| Allens Upvc Limited | Construction | 2007 |
| Alliance Carpet Mills Ltd | Real estate | 1990 |
| Alliance Carpets Ltd | Wholesale & retail | 2009 |
| Alnizeze Limited | Hospitality | 2023 |
| Amarok Systems Ltd | Other services | 2018 |
| Amed Regulatory Ltd | Public administration | 2019 |
| Amifa Financial Engineering Limited | Financial services | 2015 |
| Amifa Limited | Professional & scientific | 2001 |
| AMK Property Rentals Ltd | Real estate | 2024 |
| Amwriting Ltd | Information & communication | 2019 |
| AN Data Solutions Ltd | Information & communication | 2026 |
| Anvache Carpentry & Construction Limited | Manufacturing | 2020 |
| Anvache Properties Limited | Real estate | 2024 |
| AP Clerk of Works Services Limited | Construction | 2017 |
| Apex Clothes Ltd | Wholesale & retail | 2025 |
| Apex Fleet Management Ltd | Wholesale & retail | 2026 |
| Apex Power Solutions Ltd | Manufacturing | 2022 |
| Apollo Property Investing Ltd | Real estate | 2019 |
| Appleby Groundworks Ltd | Water & waste | 2022 |
| AR BEN Y BYD CIC | Wholesale & retail | 2026 |
| Arch Holdings (SW) Ltd | Financial services | 2019 |
| Arch Rail Services Limited | Construction | 2018 |
| Arch Utility Services (SW) Ltd | Construction | 2015 |
| ARI Distribution Ltd | Transport & logistics | 2018 |
| ARI Recruitment Ltd | Administrative & support | 2021 |
| Armaanjudge Ltd | Wholesale & retail | 2022 |
| Asgv Properties Ltd | Real estate | 2024 |
| Ashford Care Ltd | Health & social care | 2023 |
| Astrocymru Ltd | Education | 2017 |
| Avant Theatre CIC | Arts & recreation | 2017 |
| AVE Maria Enterprises Ltd | Hospitality | 2024 |
| Aztec Coatings Ltd | Construction | 2011 |
| B & D Garage Services Limited | Wholesale & retail | 2018 |
| B & E Fitness Equipment Ltd | Wholesale & retail | 2019 |
| B. J. Letting & Development Limited | Real estate | 2003 |
| B.B.Civils & Labour Ltd | Construction | 2021 |
| Bahay Property Ltd | Real estate | 2022 |
| Bailey Construction & Civils Limited | Construction | 2008 |
| Bajwa Convenience Store Limited | Wholesale & retail | 2015 |
| Bala PVT Ltd | Wholesale & retail | 2025 |
| Bargain Booze (Porth) Limited | Wholesale & retail | 2016 |
| Beechwood Memorials Ltd | Manufacturing | 2023 |
| Beefy's Baps Limited | Hospitality | 2026 |
| Beeing ME Ltd | Health & social care | 2019 |
| Belladig Digger Services Ltd | Construction | 2025 |
| Belmont Developments Limited | Other services | 2003 |
| Best Cutz 4 Ltd | Other services | 2026 |
| Beunique Wigs by Charlotte Ltd | Other services | 2025 |
| Big Al's Vending Ltd | Wholesale & retail | 2026 |
| Big Spuds Properties Limited | Real estate | 2024 |
| Bikesecure Ltd | Wholesale & retail | 2025 |
| Bk&I Holdings Ltd | Hospitality | 2023 |
| Black-Book Delivery Solutions Ltd | Transport & logistics | 2019 |
| Blooming DB Ltd | Hospitality | 2021 |
| Blue Flame GAS Solutions Limited | Construction | 2015 |
| Boldly Go Limited | Wholesale & retail | 2024 |
| Boo's Biscuits Ltd | Manufacturing | 2025 |
| Bowen 247 Limited | Professional & scientific | 2025 |
| Bright Leaf Limited | Education | 2014 |
| Brookmans Electrical Wholesalers Limited | Wholesale & retail | 2006 |
| Brookmans Property Development Limited | Construction | 2014 |
| Brown Electrical Electronics Technology Limited | Manufacturing | 2024 |
| Brush N Bloom Limited | Manufacturing | 2025 |
| Build Nexus Ltd | Real estate | 2025 |
| Business Energy Experts Ltd | Other services | 2013 |
| Business Support Centre Ltd | Professional & scientific | 2012 |
| C 2 Groundworks Limited | Construction | 2014 |
| C H Mortgages Ltd | Financial services | 2020 |
| C J H Rail Services Limited | Construction | 2018 |
| C John & Sons Ltd | Construction | 2017 |
| C T E Transport Limited | Transport & logistics | 2019 |