| Barricode Ltd | London | 2025 |
| Barrie Road 1970 Limited | Swadlincote | 2014 |
| Barrier Concepts Limited | Walsall | 2011 |
| Barrierfold Limited | Purfleet | 2009 |
| Barrington Broadcasting Limited | St. Ives | 2022 |
| Barrington Farm Social Enterprise Limited | Norwich | 2011 |
| Barrington Mews RTM Company Limited | Brackley | 2014 |
| Barringtons (Chesterfield) Limited | Bradford | 1999 |
| Barron Analytical Limited | Newbury | 1994 |
| Barron of London Limited | Sidcup | 2012 |
| Barros Group (UK) Ltd | London | 2010 |
| Barrow 1962 Limited | Thetford | 2014 |
| Barrow Hill Veterinary Group Ltd | Bristol | 2011 |
| Barrow Mill Ltd | Birmingham | 2020 |
| Barrowell Green Management Company Limited | | 1986 |
| Barrowgate Developments Limited | Callington | 2012 |
| Barrtrans Limited | Oban | 2022 |
| Barry (Muckenaugh) Limited | Swindon | 2007 |
| Barry Avenue 1962 Limited | Bicester | 2014 |
| Barry Brickwork Limited | Dunstable | 2014 |
| Barry Computer Centre Ltd | Cardiff | 2016 |
| Barry Frederick Pugh Ltd | Whitstable | 2025 |
| Barry Noble Enterprises | Gateshead | 1979 |
| Barry Noble Unlimited | Harrogate | 2000 |
| Barry Pritchard Funeral Services Limited | Nottingham | 2013 |
| Bars and Rooms at NO 18 Ltd | Dunfermline | 2020 |
| Barsby Rowe Limited | London | 1986 |
| Barston Holdings Limited | London | 2018 |
| Barstow and Portland Limited | Swansea | 2016 |
| Bartech Marine Engineering Limited | Colchester | 1998 |
| Bartholomew Trading Limited | Kettering | 2018 |
| Bartlett 61 Limited | Bournemouth | 2014 |
| Bartlett Co. (Gooderstone) Limited | Chatteris | 2001 |
| Bartlett Publications & Products Ltd | Southampton | 2006 |
| Bartlett Triathlon Limited | Loughborough | 2018 |
| Bartletts Limited | London | 1992 |
| Bartlett’S Childers Limited | Newbury | 2022 |
| Bartol Transport Ltd | West Bromwich | 2014 |
| Barton Autos Limited | Bradford | 2015 |
| Barton Broads Limited | Atherstone | 1973 |
| Barton Building Contractors Limited | Barton-Upon-Humber | 1986 |
| Barton Business Park Property Management Limited | Birmingham | 2004 |
| Barton Construction (Kettering) Limited | Kettering | 1982 |
| Barton Estates (Torquay) Limited | Nicholson Road Torquay | 1954 |
| Barton Grange Garden Centre Limited | Preston | 1974 |
| Barton Lane Management Company Limited | Leeds | 2015 |
| Barton Lodge Care Home Ltd | Eastleigh | 2017 |
| Barton Mews Management Company Limited | Penzance | 2011 |
| Barton Property Developers Ltd | Bridgwater | 2020 |
| Barton Road 1961 Limited | Luton | 2014 |
| Barton Trustee Limited | Bristol | 2020 |
| Bartonvale Ltd | Enfield | 2006 |
| Barts Limited | Maldon | 2007 |
| Bartups (Aberdeen) Ltd | Hereford | 2008 |
| Bartups (Hereford) Limited | Hereford | 1932 |
| Bartys Ltd | Kirkcaldy | 2023 |
| Barullo Limited | London | 2019 |
| Barvakten I Boras Limited | London | 2024 |
| Barwell Business Park Nominee Limited | London | 2000 |
| Barwick 1967 Limited | Stockton-On-Tees | 2013 |
| Barzey Advisory Limited | Southampton | 2013 |
| BAS & Pearl Limited | London | 2021 |
| BAS Account Services Ltd | Armagh | 2010 |
| BAS Accountancy & Tax Services Ltd | Aylesbury | 2016 |
| BAS Accounting Services Ltd | Aylesbury | 2020 |
| BAS Tax & Accountancy Services Ltd | Aylesbury | 2016 |
| Basars Maritime Ltd | Bromley | 2026 |
| Basasar Limited | Bromley | 2023 |
| Basbito ET EL Ltd | South Yorkshire | 2007 |
| Bascombe Contractors Limited | Wimborne | 2009 |
| Base 4 Plumbing & Heating Ltd | York | 2013 |
| Base Apartments Ltd | Liverpool | 2017 |
| Base Built Limited | London | 2015 |
| Base Chemical Co., Ltd | Beckenham | 2023 |
| Base Eco Limited | Leicester | 2013 |
| Base Industries Limited | Warrington | 2018 |
| Base Metal Refining Ltd | Manchester | 2014 |
| Base Properties Limited | Liverpool | 2008 |
| Base Sport Holdings Limited | London | 2019 |
| Base Supplies Limited | Uxbridge | 2021 |
| BASE10 Accounting Limited | London | 2023 |
| Basel Yachting Ltd | London | 2023 |
| Basepoint Limited | London | 1988 |
| Basepower RR Solar Limited | London | 2023 |
| Baserange International Holding Group Co., Ltd | Cambridge | 2020 |
| Basetek (Marine) Limited | Ipswich | 2008 |
| Basevilla Limited | Erith | 2009 |
| Basford Plant Ltd. | Eastwood | 1986 |
| Bash-P International Ltd | Birkenhead | 2002 |
| Basic Element Limited | Barnet, | 2009 |
| Basic Principles Limited | Huddersfield | 2005 |
| Basicconfidence Ltd | London | 2022 |
| Basil & Crust Ltd | Wolverhampton | 2025 |
| Basil 1962 Limited | Thornton Heath | 2013 |
| Basil Clarke Limited | London | 2013 |
| Basil N Crust Ltd | Wolverhampton | 2025 |
| Basil N Dough Ltd | Wolverhampton | 2025 |
| Basildon and District Local Enterprise Agency Limited | Wickford | 1984 |
| Basim Karbalaei Media Limited | London | 2015 |
| Basing Park Limited | Alton | 2009 |