| BDV Atlantic Ltd | Construction | 2014 |
| BDV Platinum Ltd | Construction | 2015 |
| BDV Sapphire Ltd | Construction | 2015 |
| Bdwshop Ltd | Wholesale & retail | 2025 |
| BE Brave - Daycare and Cyber Safety Ltd | Education | 2025 |
| BE Business Fit Ltd | Professional & scientific | 2020 |
| BE Covered Ltd | Financial services | 2024 |
| BE Eco Energy Limited | Manufacturing | 2024 |
| BE Elite GK Limited | Wholesale & retail | 2017 |
| BE Fit & Muscular Ltd | Wholesale & retail | 2018 |
| BE Foods Ltd | Wholesale & retail | 2018 |
| BE Kind Cleaning Services Limited | Administrative & support | 2025 |
| BE Lean Agile Ltd | Information & communication | 2018 |
| BE Love Community CIC | Hospitality | 2026 |
| BE Recruiting Ltd | Administrative & support | 2023 |
| BE Recruitment Staffing Ltd | Administrative & support | 2021 |
| BE Successful Ltd | Information & communication | 2019 |
| BE the Creator Limited | Wholesale & retail | 2021 |
| BE the Winner Ltd | Arts & recreation | 2025 |
| BE Versatile Limited | Other services | 2016 |
| Beaacce Store Ltd | Wholesale & retail | 2024 |
| Beaback Sales Ltd | Wholesale & retail | 2024 |
| Beach Leisure Limited | Other services | 2002 |
| Beacon Bailey Homes Limited | Real estate | 2020 |
| Beacon Centre Trust (Cardiff) | Real estate | 1999 |
| Beacon Developments Cardiff Limited | Real estate | 2018 |
| Beacon MED Staffing Limited | Health & social care | 2019 |
| Beacon Solar Limited | Energy | 2024 |
| Beacon Square Investments Ltd | Real estate | 2022 |
| Beacon Tuition Centre CIC | Education | 2008 |
| Beacon View Healthcare Limited | Health & social care | 2015 |
| Beacon View Systems Ltd | Information & communication | 2025 |
| Beaconline Saas Limited | Information & communication | 2025 |
| Beacons Development Ltd | Construction | 2024 |
| Beag Investments Limited | Professional & scientific | 2017 |
| Beam Beauty and Body Care Ltd. | Wholesale & retail | 2020 |
| Beam Development and Training Ltd | Education | 2017 |
| Beam Project Management Ltd | Professional & scientific | 2025 |
| Beamat Investments Ltd | Financial services | 2018 |
| Beamazed Events Limited | Other services | 2017 |
| Beamedi Limited | Health & social care | 2015 |
| Bean's to Coffee Ltd | Hospitality | 2023 |
| Beanfreaks Limited | Wholesale & retail | 1987 |
| Beanity Coffee Ltd | Hospitality | 2018 |
| Beans to Coffee @ the Hall Ltd | Hospitality | 2025 |
| Beapak Packaging Limited | Wholesale & retail | 2019 |
| Bear and Moose Limited | Professional & scientific | 2020 |
| Bear Architectural Recruitment Limited | Administrative & support | 2019 |
| Bear Corner Limited | Hospitality | 2026 |
| Bear Industrial Engineering Limited | Professional & scientific | 2016 |
| Bear With ME Books Ltd. | Information & communication | 2016 |
| Bearbones 4X4 Ltd | Wholesale & retail | 2019 |
| Beardy Chef Limited | Hospitality | 2025 |
| Bearhart Ltd | Arts & recreation | 2025 |
| Bearmark Properties Ltd | Real estate | 2026 |
| Bears Barbershop Ltd | Other services | 2020 |
| Bears Wealth Limited | Manufacturing | 2024 |
| Bearstock Property Limited | Construction | 2018 |
| Beat the Business Limited | Wholesale & retail | 2022 |
| Beato Solutions Ltd | Wholesale & retail | 2025 |
| Beatrice Rose Care Group Limited | Health & social care | 2004 |
| Beattie Energy Solutions Limited | Administrative & support | 2011 |
| Beatz Studios Ltd | Information & communication | 2025 |
| Beau Domicile Ltd | Real estate | 2019 |
| Beau Properties Cardiff Ltd | Real estate | 2024 |
| Beauchamp Residential Ltd | Real estate | 2018 |
| Beaudeville Property Group Ltd | Real estate | 2019 |
| Beaudrey (UK) Limited | Construction | 2009 |
| Beaufort Research Employee Ownership Trustee Limited | Professional & scientific | 2024 |
| Beaufort Research Holdings Limited | Financial services | 2014 |
| Beaufort Research Limited | Professional & scientific | 1985 |
| Beaufort Supplies Limited | Administrative & support | 2015 |
| Beaumont 2000 Ltd | Administrative & support | 2025 |
| Beaumont Bale Ltd | Real estate | 2022 |
| Beaumont Beverages Ltd. | Wholesale & retail | 2017 |
| Beaumont Chambscrow Limited | Professional & scientific | 2021 |
| Beaumont Consultancy Limited | Professional & scientific | 2014 |
| Beaumont Partnership Ltd | Administrative & support | 2009 |
| Beaumont Scaffolding Services Ltd | Construction | 2019 |
| Beaupeau Limited | Wholesale & retail | 2025 |
| Beautiful Beauty 4U Ltd | Other services | 2024 |
| Beautiful Estates Group Ltd | Real estate | 2017 |
| Beautilio Limited | Information & communication | 2019 |
| Beauty 24 Limited | Administrative & support | 2023 |
| Beauty Advance Skin & Laser Clinic Limited | Other services | 2002 |
| Beauty at Highfield Ltd | Other services | 2015 |
| Beauty Box Aesthetics (Cardiff) Ltd | Other services | 2021 |
| Beauty Enhance Limited | Other services | 2025 |
| Beauty FLY Food Limited | Wholesale & retail | 2021 |
| Beauty Getaway Ltd | Other services | 2023 |
| Beauty Group GmbH Ltd | Wholesale & retail | 2025 |
| Beauty GSK Limited | Wholesale & retail | 2025 |
| Beauty Lash and Eyebrows Ltd | Other services | 2023 |
| Beauty Nails Canton Ltd | Other services | 2019 |
| Beauty Pulsetech Ltd | Health & social care | 2025 |
| Beauty Room Cardiff Limited | Other services | 2025 |
| Beauty Success European Ltd | Wholesale & retail | 2025 |
| Beauty Tips Ltd | Other services | 2019 |
| Beauty World Training Academy Limited | Education | 2021 |
| Beautybookd Ltd | Information & communication | 2026 |