| Beyond the Skills Limited | Administrative & support | 2023 |
| Bijou Jewellers Ltd | Wholesale & retail | 2024 |
| Billiard CUE Enterprises Limited | Extraterritorial | 1999 |
| Bison Industrial Doors Limited | Construction | 2018 |
| Bits N Bobs (Birmingham) Limited | Wholesale & retail | 2019 |
| Blackrock Business & Consultancy Services Limited | Information & communication | 2007 |
| Blackrock Mortgages & Protection Limited | Financial services | 2026 |
| Bloodworths Hardware & DIY Limited | Wholesale & retail | 2018 |
| BLU Violet Solution Limited | Construction | 2023 |
| Bluebusbakes Catering Ltd | Hospitality | 2025 |
| Bonnie Property Management Limited | Households | 2024 |
| BOO With Attitude Limited | Manufacturing | 2022 |
| Boobeads Ltd | Manufacturing | 2024 |
| Boughspring Solutions Limited | Information & communication | 2003 |
| Bouncing Dragons Hire and Supply Ltd | Wholesale & retail | 2021 |
| Boxistore Limited | Transport & logistics | 2018 |
| Bradburys Farm Management Ltd | Professional & scientific | 2017 |
| Bradshaw Property Limited | Real estate | 2017 |
| Bragg Family Capital Ltd | Wholesale & retail | 2023 |
| BRD Roofing Limited | Construction | 2019 |
| BRD Waste Solutions Limited | Water & waste | 2020 |
| Brian Stephenson Limited | Health & social care | 2014 |
| Brigid Counselling and Psychotherapy Services Ltd | Health & social care | 2023 |
| Bristol Storage Solutions Limited | Transport & logistics | 2026 |
| Broadlands Accounting Solutions Limited | Professional & scientific | 2007 |
| Broadrock Lodge Ltd | Hospitality | 2018 |
| Brockley Stores Ltd | Wholesale & retail | 2015 |
| Bromleighs Limited | Wholesale & retail | 2009 |
| Broome & Company Limited | Agriculture & fishing | 1972 |
| Brushed UP Ltd | Administrative & support | 2021 |
| Buildsafe Trading LLP | | 2011 |
| Business Detectives Limited | Administrative & support | 2010 |
| C&Hc Limited | Professional & scientific | 2011 |
| CAD Visuals Ltd | Professional & scientific | 2007 |
| Caeau Hapus Limited | Arts & recreation | 2021 |
| Caergwrle Limited | Agriculture & fishing | 2022 |
| Caerwent Craft Chocolate Ltd | Manufacturing | 2022 |
| Caerwent Playing Fields Association Limited | Arts & recreation | 2008 |
| Caldiclean Ltd | Administrative & support | 2019 |
| Caldicot 10 Ltd | Hospitality | 2025 |
| Caldicot Ltd | Hospitality | 2014 |
| Caldicot Recovery Systems Limited | Wholesale & retail | 2018 |
| Caldicot Rugby Limited | Arts & recreation | 2018 |
| Caldicot Town Team C.I.C. | Administrative & support | 2014 |
| Caldicot Trade Sales Ltd | Wholesale & retail | 2019 |
| Caldicot Youth Group | Education | 2007 |
| Caledonian Safety Solutions Ltd | Professional & scientific | 2025 |
| Camera’S Ready Ltd | Information & communication | 2025 |
| Campbell's Garden Care Limited | Other services | 2025 |
| Camster & Co Limited | Wholesale & retail | 2015 |
| Canyon Estates Ltd | Real estate | 2019 |
| Canyon Foods Ltd | Hospitality | 2022 |
| Canyon Property Management Ltd | Real estate | 2019 |
| Carbon Neutral Supplies Ltd | Wholesale & retail | 2023 |
| Carbon Neutral Systems Ltd | Construction | 2020 |
| Carboniq Ltd | Professional & scientific | 2026 |
| Cardiff Restaurant Limited | Hospitality | 2020 |
| Cartref Media Company Limited | Information & communication | 2023 |
| Casa Leisure Holdings Ltd | Real estate | 2023 |
| Castell Coffi Ltd | Hospitality | 2024 |
| Castle Phones Limited | Wholesale & retail | 2024 |
| Castlec Ltd | Wholesale & retail | 2011 |
| Catbrook Finance Limited | Financial services | 2014 |
| Cath DDU Energy Ltd | Mining & quarrying | 2014 |
| Catipilla Limited | Wholesale & retail | 2016 |
| Cautela Marketing Ltd | Professional & scientific | 2025 |
| Cayo Management Company Limited | Households | 2018 |
| CBD Consultancy Limited | Public administration | 2019 |
| Cellyne&Maria Ltd | Transport & logistics | 2025 |
| Celtic Construction Group Ltd | Construction | 2012 |
| Central Accounting Limited | Professional & scientific | 1991 |
| CG Infra Limited | Construction | 2023 |
| Cgcr Trading Ltd | Wholesale & retail | 2024 |
| Chancery Automotive Limited | Wholesale & retail | 2018 |
| Channel View Equine Retreat Ltd | Agriculture & fishing | 2020 |
| Chase ME Charlie Ltd | Professional & scientific | 2021 |
| Chep Spice Ltd | Hospitality | 2025 |
| Chepstow & District Vintage Club | Other services | 1997 |
| Chepstow Construction & Maintenance Limited | Administrative & support | 1996 |
| Chepstow Contract Rentals Limited | Administrative & support | 2001 |
| Chepstow Removals Limited | Transport & logistics | 2018 |
| Chepstow Restaurant Limited | Hospitality | 2019 |
| Chepstow Surfacing & Landscaping Ltd | Administrative & support | 2023 |
| Chepstow Trade Centre Limited | Wholesale & retail | 2016 |
| Cherry Blossom Lane Limited | Real estate | 2025 |
| Chou Chous Day Nursery Limited | Education | 2019 |
| Chris NDT Limited | Professional & scientific | 2017 |
| Chris Wheeler Signal Engineer Limited | Other services | 2000 |
| Christopher Wong Ltd | Health & social care | 2010 |
| Cineprops Ltd | Professional & scientific | 2019 |
| Citizen Kane Limited | Arts & recreation | 2016 |
| City of Newport Model Engineering Society (NOT for Profit) Limited | Manufacturing | 1995 |
| City Pictures Limited | Arts & recreation | 2015 |
| Civil Visuals Limited | Information & communication | 2021 |
| CKL Consultancy Services Limited | Professional & scientific | 2020 |
| CKM Property Group Ltd | Real estate | 2026 |
| CKS Ortho Ltd | Health & social care | 2025 |
| Classic Gardens Landscaping Limited | Administrative & support | 2021 |
| Clean&Sheen Ltd | Administrative & support | 2024 |
| Clothesforhomes Ltd | Wholesale & retail | 2026 |