| 190-192 Llandaff Road Management Company Ltd | Households | 2014 |
| 2 Live Cardiff Limited | Health & social care | 2023 |
| 2C 2D Porthycarne Street Management Company Limited | Households | 2022 |
| 35 & 37 Trinity Close Limited | Households | 2024 |
| 44 Maryport Street USK Management Limited | Households | 1988 |
| 4U2RENT Ltd | Real estate | 2022 |
| 56 Brecon Road Management Company Limited | Extraterritorial | 2005 |
| 90 Upper Tollington Park Management Company Limited | Real estate | 2008 |
| A J Hale Construction Limited | Construction | 2009 |
| A. C. E. Electrical Contracting Company Limited | Construction | 1996 |
| Abercynon Service Station Ltd | Wholesale & retail | 2026 |
| Acuphysio Limited | Health & social care | 2025 |
| Adam James Hospitality Ltd | Hospitality | 2018 |
| ADD Agency Limited | Professional & scientific | 2006 |
| Adkd Consultants Limited | Professional & scientific | 2018 |
| Advantage Asset Maintenance and Management Ltd | Real estate | 2023 |
| Agilis Sport Limited | Wholesale & retail | 2020 |
| AI Law Limited | Professional & scientific | 2016 |
| AIMS4CHANGE Ltd | Education | 2006 |
| AJ Oliver and Company Ltd | Professional & scientific | 2014 |
| AJP Innovations Limited | Extraterritorial | 2014 |
| Alambe Financial Services Limited | Professional & scientific | 2023 |
| Alcester Service Station Ltd | Wholesale & retail | 2026 |
| Alchemy Projects and Advisory Ltd | Administrative & support | 2022 |
| Alfies Fancies CYF. | Manufacturing | 2019 |
| Allt Y Bela Farm Limited | Agriculture & fishing | 2022 |
| Alpha Renewables Limited | Construction | 2009 |
| AM Logistics Group Ltd | Transport & logistics | 2019 |
| Amati Instruments Limited | Wholesale & retail | 2013 |
| Amberley Property Limited | Real estate | 2024 |
| Amok Consultancy Ltd | Professional & scientific | 2023 |
| Anthony John Hairdressing Limited | Other services | 2004 |
| Apex Brokerage Ltd | Other services | 2018 |
| Apex Financial Solutions (South Wales) Limited | Financial services | 2010 |
| Apex Mortgage Network Ltd | Other services | 2017 |
| Apsb Ltd | Wholesale & retail | 2024 |
| Arcas Design LLP | | 2020 |
| Archer & Co Lettings Ltd | Real estate | 2007 |
| Artemis Soul Sanctuary Limited | Health & social care | 2023 |
| Ascott Planning Limited | Professional & scientific | 2017 |
| ASK Education & Training Limited | Construction | 2003 |
| Asset Mortgage Solutions Limited | Financial services | 2004 |
| Authentic Pubs Limited | Hospitality | 2012 |
| Avius Aluminium Limited | Construction | 2026 |
| AWJ Property Group Ltd | Real estate | 2022 |
| AWS Welding Services Limited | Manufacturing | 2016 |
| Azimuth Land Surveys Limited | Professional & scientific | 1988 |
| Barkers Commercial Services Limited | Professional & scientific | 2018 |
| Barnabas Crest Ltd | Wholesale & retail | 2026 |
| BCZ Developments Ltd | Wholesale & retail | 2017 |
| Bear Photography Limited | Professional & scientific | 2012 |
| Beaver Framing Monmouth Ltd | Manufacturing | 2021 |
| Beechfern Limited | Real estate | 2011 |
| Beta School Limited | Education | 2006 |
| Bette LDN Limited | Professional & scientific | 2024 |
| Beverley Gateway Services Ltd | Wholesale & retail | 2026 |
| BID and Breakfast.Com Limited | Administrative & support | 2008 |
| BID Writing Services Limited | Professional & scientific | 2021 |
| Big Green Button Limited | Information & communication | 2010 |
| Black Mountains Smokery Limited | Manufacturing | 1995 |
| Blackfriars Management Company Limited | Households | 1985 |
| Blue Lagoon Management Limited | Administrative & support | 2019 |
| Bobster Consulting (INT) Ltd | Information & communication | 2019 |
| Bobster Consulting Ltd | Information & communication | 2019 |
| Bond Connect Limited | Information & communication | 2026 |
| Born Again Eco Ltd | Manufacturing | 2024 |
| Bowen Construction & Fabrication Ltd | Construction | 2017 |
| Bowman Process Technology Limited | Professional & scientific | 1997 |
| BQI Limited | Professional & scientific | 2018 |
| Bridge & Bloom Ltd | Hospitality | 2025 |
| British Bleu DU Maine Sheep Society Limited(The) | Agriculture & fishing | 1982 |
| BRK Accounting Services Limited | Professional & scientific | 2005 |
| Brook Cottage Enterprises Limited | Professional & scientific | 2011 |
| Bruce & Co (Accountancy Services) Limited | Professional & scientific | 2004 |
| Bryn Celyn Management Limited | Households | 2021 |
| BSP Technology Ltd | Extraterritorial | 2012 |
| Buckle Chamberlain Partnership Limited | Professional & scientific | 2004 |
| Burchell Properties Limited | Real estate | 2016 |
| Burgage Green Administration Limited | Real estate | 2026 |
| Burgage Green Management Company Limited | Real estate | 2005 |
| Burgage Green Management Company Number 2 Limited | Real estate | 2006 |
| Byzantine Games Limited | Information & communication | 2016 |
| C & J Barrett Ltd | Manufacturing | 2010 |
| C Thomas Leisure Limited | Hospitality | 2015 |
| Caasa Group Limited | Real estate | 2025 |
| Cadarn Developments Limited | Construction | 2025 |
| Cadno Communications Limited | Professional & scientific | 2015 |
| Cake & Counsel Limited | Health & social care | 2021 |
| Camelot Farm Services Ltd | Agriculture & fishing | 2023 |
| Cardiff Lets Ltd | Professional & scientific | 2010 |
| Cardiff Lettings Limited | Real estate | 2017 |
| Carl Betty Martial Arts Ltd | Arts & recreation | 2021 |
| Carter Loxworth Business Services Ltd | Administrative & support | 2022 |
| Cash COW Ltd | Other services | 2023 |
| Casm Property Ltd | Real estate | 2022 |
| Castell Tregrug Management Limited | Households | 2020 |
| Castle Electrics Limited | Construction | 2018 |
| Castle Maintenance Raglan Ltd | Administrative & support | 2019 |
| Catherine and Michael John Limited | Hospitality | 2007 |
| Cbsb Consulting Limited | Professional & scientific | 2023 |