| 'Aspirations' Independent Social Work & Training Services Limited | Health & social care | 2025 |
| 08 Martial Arts Clothing & Equipment Ltd | Wholesale & retail | 2026 |
| 23CP Property Limited | Real estate | 2021 |
| 59 Eynham Road London Management Company Limited | Households | 2007 |
| 73 Group Global Ltd | Information & communication | 2004 |
| 75 Eastgate Management Company Limited | Real estate | 2023 |
| 79, 73 and 67 Halliard Court Limited | Households | 2014 |
| Abigail Walker Lingerie Limited | Manufacturing | 2022 |
| Able Wellness Talking Therapies Limited | Extraterritorial | 2023 |
| Abney Construction Limited | Construction | 2003 |
| Abraxas Ecology Limited | Professional & scientific | 2015 |
| ACCENTU8 Limited | Manufacturing | 2014 |
| ACTIVE4SPORT International Ltd | Arts & recreation | 2022 |
| Acura Mortgage & Life Ltd | Financial services | 2024 |
| Acura Wealth Ltd | Financial services | 2021 |
| Adam Elliot Limited | Manufacturing | 2014 |
| Adey Fitzgerald and Walker Ltd | Professional & scientific | 2023 |
| Adey, Fitzgerald & Walker (Cowbridge) Ltd | Professional & scientific | 2015 |
| ADJ Protection Ltd | Administrative & support | 2021 |
| ADM Bros Ltd | Real estate | 2026 |
| After My Days Limited | Extraterritorial | 2022 |
| Air MAX Limited | Other services | 1993 |
| Akshara Living Ltd. | Professional & scientific | 2015 |
| Alcolyser Limited | Manufacturing | 1980 |
| Alex Plant Limited | Professional & scientific | 2003 |
| Alexiom Business Partners Limited | Professional & scientific | 2020 |
| ALL CAN Drive Ltd. | Education | 2019 |
| ALL for Food Limited | Hospitality | 2008 |
| Ally Merchant HR Consultancy Ltd | Professional & scientific | 2025 |
| AM Properties (South Wales) Limited | Real estate | 2016 |
| Amanda LOU Events Limited | Professional & scientific | 2014 |
| AMD Communications Ltd | Professional & scientific | 2022 |
| Amelioraid Limited | | 1997 |
| Andrew & James Partnership Limited | Professional & scientific | 2002 |
| Andrew Langston Limited | Health & social care | 2007 |
| Andrew Smith Marketing Ltd | Professional & scientific | 2019 |
| Andrew Thomas Property Consultant Limited | Real estate | 1998 |
| Angling (Imports) Ltd | Wholesale & retail | 2013 |
| Annette I Dobbs Limited | Health & social care | 2013 |
| Anthony G.Martin Limited | Health & social care | 2008 |
| Anthony O'Sullivan Limited | Construction | 2004 |
| Applied Automation Services Ltd | Information & communication | 2015 |
| Apure Property Management Limited | Real estate | 2018 |
| Artizan Leisure Limited | Hospitality | 2001 |
| Ashdown Construction Group Limited | Manufacturing | 2005 |
| Ashdown Timber Frame Limited | Manufacturing | 2021 |
| Ashfort Consulting Ltd | Professional & scientific | 2023 |
| Asource Limited | Wholesale & retail | 2023 |
| Aspect Insulation Solutions Limited | Construction | 2021 |
| Association of Wholesale Electrical Bulk Buyers Limited | Wholesale & retail | 1976 |
| Aston Investment Group Ltd | Financial services | 2023 |
| ATX Consulting Ltd | Professional & scientific | 2026 |
| Augusta Court Management Company Limited | Households | 2016 |
| Austin HIP Solutions Limited | Administrative & support | 2010 |
| Austin Rover Cars Ltd | Wholesale & retail | 2024 |
| Austin Rover Group Ltd | Wholesale & retail | 2024 |
| Austin Rover Motorsport Ltd | Wholesale & retail | 2024 |
| Autolex Limited | Construction | 2007 |
| Autoworx Repair Centre Ltd | Wholesale & retail | 2026 |
| Avarch Creatives Limited | Information & communication | 2020 |
| Avid & GEM Acquisitions Limited | Wholesale & retail | 2006 |
| Aztec Joinery Limited | Manufacturing | 2018 |
| B.& C.Finance Limited | Professional & scientific | 1955 |
| Backed by Frank Limited | Financial services | 2026 |
| Badger Special Projects Limited | Financial services | 2026 |
| Bamboo Group Holdings Limited | Financial services | 2021 |
| Bamboo Law Ltd | Professional & scientific | 2021 |
| Bannr Limited | Financial services | 2026 |
| Barley MOW Inn (Graig Penllyn) Ltd | Hospitality | 2023 |
| Basic Commands Ltd | Education | 2025 |
| Bates Cass Consulting Limited | Professional & scientific | 2020 |
| Bayside Garage Ltd | Wholesale & retail | 2007 |
| BCH Solutions Limited | Professional & scientific | 2009 |
| Bear Strength Limited | Wholesale & retail | 2013 |
| Beat Down Events Ltd | Arts & recreation | 2026 |
| BEE & Bloom Baby Ltd | Wholesale & retail | 2023 |
| Bentash Property Ltd | Real estate | 2025 |
| Bestie UK. Ltd | Wholesale & retail | 2017 |
| Bethuels Court (Cowbridge) Limited | Real estate | 2024 |
| BI Contractors Limited | Information & communication | 2012 |
| Bi-Pro Services Limited | Manufacturing | 2017 |
| Bijou Day Nursery and Creche Ltd | Education | 2018 |
| Bijou Nursery Holdings Limited | Financial services | 2023 |
| Bilko's Mighty Meats Ltd | Manufacturing | 2026 |
| Black Dragon Cider Ltd | Hospitality | 2016 |
| Blendini Motorsport Logistics Limited | Wholesale & retail | 2025 |
| Blendini MS Limited | Wholesale & retail | 2014 |
| Blue Bay Consolidated Investments Limited | Real estate | 2005 |
| Bluebell Renovation Ltd | Construction | 2025 |
| Bluebucket PR and Marketing Limited | Administrative & support | 2013 |
| Bluecore Labs Ltd | Information & communication | 2024 |
| Bluemoose Digital Ltd | Information & communication | 2025 |
| Blwbo Limited | Professional & scientific | 2017 |
| BMI Vision Ltd | Information & communication | 2010 |
| Bravonix Ltd | Wholesale & retail | 2024 |
| Brecon Estates (UK) Limited | Real estate | 2017 |
| Bridal Edit Outlet Cowbridge Ltd | Wholesale & retail | 2025 |
| Bridge FM Radio Limited | Information & communication | 1999 |
| Bridgend Anaesthetists Limited | Health & social care | 2003 |
| Bridgend Fabrics Ltd | Wholesale & retail | 2013 |