| Ashford Ross Ltd | Wholesale & retail | 2024 |
| Ashley at the Unicorn Ltd | Hospitality | 2018 |
| Ashton James Homes UK Limited | Construction | 2023 |
| Ashton Plant Ltd | Administrative & support | 2024 |
| Asphalia Food Products Limited | Manufacturing | 2007 |
| Aston Acres Ltd | Wholesale & retail | 2025 |
| Astrid Schon Education Consultancy Ltd | Education | 2026 |
| Atoz Deals Ltd | Wholesale & retail | 2023 |
| ATT Property Investments Group Ltd | Hospitality | 2025 |
| Auden Hazel Ltd | Wholesale & retail | 2025 |
| AV Group Limited | Wholesale & retail | 2019 |
| AW Estate Holdings Limited | Real estate | 2023 |
| AW6 Promotions Limited | Arts & recreation | 2019 |
| AXO LAB Ltd | Information & communication | 2025 |
| B Pearson Holdings Ltd | Real estate | 2021 |
| B&M Fish and Chip Company Limited | Wholesale & retail | 2015 |
| B.A.N.C. Convenience Store Limited | Wholesale & retail | 2005 |
| B124U Ltd | Health & social care | 2021 |
| Bacaro Wharf Ltd | Wholesale & retail | 2025 |
| Back and Forth Executive Travel Ltd | Transport & logistics | 2026 |
| Baffle Culture Limited | Wholesale & retail | 2020 |
| Bagshaw Glen Ltd | Wholesale & retail | 2025 |
| Baha Barbers Ltd | Other services | 2024 |
| Bailey Bridge Consultancy Ltd | Professional & scientific | 2017 |
| Baked by Bridge Ltd | Manufacturing | 2026 |
| Baker Street Y-Fenni Holdings Limited | Hospitality | 2017 |
| Baker Timber Agents Limited | Wholesale & retail | 2013 |
| Bakestone Bakery Limited | Manufacturing | 2012 |
| Balfour Anchor Ltd | Wholesale & retail | 2025 |
| Ballyilltyd Ltd | Real estate | 2022 |
| Bancroft Property Investments Ltd | Real estate | 2023 |
| Bancroft Property Services Limited | Construction | 2018 |
| Bangor Grove Ltd | Wholesale & retail | 2025 |
| Barnabas Francis Ltd | Wholesale & retail | 2024 |
| Barnard Swift Ltd | Wholesale & retail | 2025 |
| BBS Surveyor Ltd | Information & communication | 2020 |
| BC05 Associates Ltd | Arts & recreation | 2022 |
| BCD Contracting Services Ltd | Water & waste | 2015 |
| Bcfb Trading Limited | Professional & scientific | 2026 |
| BE Sure Construction Ltd | Construction | 2023 |
| BE Your Own Role Model CIC | Education | 2025 |
| Beach Kids Ltd | Wholesale & retail | 2024 |
| Beacham's Elite Mortgages Limited | Financial services | 2013 |
| Beachcroft Hopper Ltd | Wholesale & retail | 2025 |
| Bear HUG Sports Ltd | Wholesale & retail | 2016 |
| Beauty Oasis SJP Ltd | Other services | 2009 |
| Bebhionn Consulting Limited | Professional & scientific | 2026 |
| Beckett & Co Accountants Ltd | Extraterritorial | 2018 |
| Beckett & Partners Ltd | Extraterritorial | 2018 |
| Beijing House 36 Limited | Hospitality | 2023 |
| Bellmoore Victor Ltd | Wholesale & retail | 2025 |
| Belmont North Ltd | Wholesale & retail | 2025 |
| Bembridge Halls Ltd | Wholesale & retail | 2025 |
| Beneil Media Ltd | Wholesale & retail | 2023 |
| Benored Ltd | Information & communication | 2025 |
| Bespoke Bathrooms (Cwmbran) Limited | Construction | 2022 |
| Bespoke Construction & Joinery Solutions Limited | Construction | 2020 |
| Bespoke Maintenance & Facilities Management Limited | Construction | 2026 |
| Best Friend 1175 Ltd | Wholesale & retail | 2025 |
| Beth Jones Properties Limited | Real estate | 2015 |
| Bewitching Wind Farm Ltd | Agriculture & fishing | 2023 |
| Big Dog Timber Ltd | Wholesale & retail | 2025 |
| Big Eyed Deer Ltd | Professional & scientific | 2022 |
| Birch & Brick Ltd | Households | 2025 |
| Birch House Management Company Limited | Households | 2016 |
| Black Dragon Group Ltd | Wholesale & retail | 2025 |
| Blackwell Heating and Plumbing (Wales and South West) Ltd | Construction | 2026 |
| Blaenavon Workmens Hall Limited | Arts & recreation | 2017 |
| Blindside Design Limited | Wholesale & retail | 2020 |
| Blitz Media Limited | Professional & scientific | 2010 |
| Blossom House Enterprises Limited | Construction | 2023 |
| Blossom Massage Ltd | Other services | 2025 |
| BLT Scaffolding Ltd | Construction | 2021 |
| Blue Cherry Limited | Transport & logistics | 2025 |
| BMG Construction (MB) Limited | Construction | 2022 |
| Border Nurseries Limited | Extraterritorial | 2010 |
| Boucher Communications Ltd | Information & communication | 2024 |
| BOW WOW !WOW! Ltd | Other services | 2020 |
| Box’D Bar & Pizza Ltd | Manufacturing | 2023 |
| Bracey Dental Limited | Health & social care | 2017 |
| Braemar Lemon Ltd | Wholesale & retail | 2025 |
| Brambles Builders Ltd | Construction | 2020 |
| Brandford Spencer Ltd | Wholesale & retail | 2025 |
| Branksome Wells Ltd | Wholesale & retail | 2025 |
| Bree (Wales) Limited | Construction | 2014 |
| Brewers Hold Ltd | Wholesale & retail | 2025 |
| Breydon Lush Ltd | Wholesale & retail | 2025 |
| Brick Fabrication Limited | Manufacturing | 1997 |
| Brickcraft Building and Civil Engineering Ltd | Construction | 2002 |
| Brickfab Cladding Systems Limited | Manufacturing | 2019 |
| Brickfab GRP Limited | Manufacturing | 2019 |
| Bridge 48 Ltd | Hospitality | 2023 |
| Bridge Lines Limited | Wholesale & retail | 2023 |
| Brighter Being Ltd | Education | 2025 |
| Brightwell Foster Ltd | Wholesale & retail | 2025 |
| Bristol Bath Builders Ltd | Construction | 2020 |
| Broadleaf Arboriculture Services Ltd | Administrative & support | 2022 |
| Bronllys Property Management Limited | Households | 2025 |
| Brooklyn Morley Ltd | Wholesale & retail | 2025 |
| Bryn Derwen Limited | Real estate | 1997 |