| Birchen Limited | Brough | 2014 |
| Birchenwood Project Services Limited | Stoke-On-Trent | 2007 |
| Birchfield Sheet Metal Engineering Company Limited | London | 2008 |
| Birchills Automotive (Presswork) Limited | Walsall | 1964 |
| Birchills Joinery Products Limited | Walsall | 2002 |
| Birchills Sculptures & Metal Restorations Limited | Walsall | 2021 |
| Birchley Supplies Ltd | Coventry | 2013 |
| Birchprint Limited | Market Drayton | 2002 |
| Birchway Electrical Services Limited | Mansfield | 2023 |
| Birchwells Spas Limited | Worksop | 2025 |
| Birchwood Bespoke Joinery Limited | Nottingham | 2017 |
| Birchwood Joinery Limited | Newry | 2024 |
| Birchwood Manufacturing Ltd | Belfast | 2024 |
| Birchwood Pharma Ltd | Dartford | 2011 |
| Birchwood Saddle Trees Ltd | Norton Canes | 2023 |
| Bird & Blend Tea Ltd. | Worthing | 2013 |
| Bird & Branch Ltd | St. Leonards-On-Sea | 2015 |
| Bird AHU Services Ltd | Huddersfield | 2025 |
| Bird Box Multi Tool Ltd | Rickmansworth | 2021 |
| Bird Brain Bakery Ltd | Stockport | 2024 |
| Bird Control Systems Limited | Fordingbridge | 2013 |
| Bird Cycleworks Ltd | Consett | 2013 |
| Bird Foliage Limited | London | 2019 |
| Bird House Brewing Company Ltd | London | 2022 |
| Bird in the Hand Limited | London | 2008 |
| Bird of Paradise Ltd | London | 2026 |
| Bird Wellbeing Ltd | Bournemouth | 2025 |
| Bird's Pottery Ltd | Cinderford | 2024 |
| Bird-Friendly Farm Management Ltd. | Taunton | 2019 |
| Birdbox Brewery Ltd | Manchester | 2021 |
| Birdbrook Rosettes Limited | Lincoln | 2011 |
| Birdcage Bridal Boutique Limited | Welwyn Garden City | 2017 |
| Birdcage Walk Limited | Exeter | 2025 |
| Birdhouse Tea & Bakes Ltd | Rotherham | 2025 |
| Birdhouse Tea Company Limited | Rotherham | 2013 |
| Birdie London Limited | London | 2017 |
| Birdie's Natural Juice Ltd | London | 2026 |
| Birdlow Mane Limited | Isleworth | 2025 |
| Birdon (UK) Limited | London | 2014 |
| Birds (Derby) Limited | | 1930 |
| Birds Bakery Holdings Ltd | Derby | 2022 |
| Birds EYE Limited | Woking | 1938 |
| Birds Machinery Services Limited | Sutton Coldfield | 2005 |
| Birds Precision Engineering Limited | Nuneaton | 2002 |
| Birdwells Services Ltd | Sheffield | 2022 |
| Birdwood Games Ltd | Leamington Spa | 2020 |
| Birdy Blacksmiths Ltd | Banbury | 2026 |
| Birdy Boat Repairs Ltd | Lee-On-The-Solent | 2025 |
| Birdy's Ltd | Saffron Walden | 2007 |
| Birford Cable & Harness Limited | Wolverhampton | 1978 |
| Biri Foods Ltd | Solihull | 2026 |
| Biri Solution Limited | Chester | 2026 |
| Birkbeck Commercials Limited | Carlisle | 2016 |
| Birkbeck Design Engineering UK Ltd | London | 2024 |
| Birkbeck Group Ltd | London | 2026 |
| Birkbeck Structures Limited | Bradford | 2016 |
| Birkdale Plastics Limited | Chorley New Road Horwich | 1996 |
| Birken Tree (Scotland) Limited | Dunkeld | 2019 |
| Birkenhead Brewery Company Ltd | Wirral | 2018 |
| Birkenhead Monumental Limited | Prenton | 1999 |
| Birkenhead Powder Coatings Limited | | 2006 |
| Birkett Abrasive Machinery Ltd | Leeds | 2025 |
| Birkett Electric Limited | Walsall | 1978 |
| Birkett Steel Engineering Ltd | Keswick | 2024 |
| Birkett-Ycol Limited | Staffordshire | 1936 |
| Birkin & Couper Ltd | Borehamwood | 2022 |
| Birksteinotler Ltd | Northwich | 2022 |
| Birley Manufacturing Limited | Leeds | 1999 |
| Birlim Litho (2007) Limited | Nottingham | 2007 |
| Birlinn Offshore Limited | Inverness | 2016 |
| Birmingham Metal Co Limited | Birmingham | 1987 |
| Birmingham Air Conditioning Services Limited | Birmingham | 2002 |
| Birmingham Air Services Limited | | 2008 |
| Birmingham Aluminium Systems (BAS) Ltd | Birmingham | 2020 |
| Birmingham Billiards Limited | Walsall | 1982 |
| Birmingham Biomat Ltd | Birmingham | 2025 |
| Birmingham Biotech Ltd | Birmingham | 2020 |
| Birmingham Blinds Limited | Birmingham | 2000 |
| Birmingham Brewing Company Limited | Birmingham | 2016 |
| Birmingham Burner (Walsall) Limited | Walsall | 1978 |
| Birmingham Busworks Limited | Birmingham | 2021 |
| Birmingham Case Makers Limited | Bromsgrove | 2012 |
| Birmingham Catering Equipment Limited | Birmingham | 1993 |
| Birmingham Central Kitchen Limited | Birmingham | 2026 |
| Birmingham City Glass Ltd | Kenilworth | 2026 |
| Birmingham CNC Machines Ltd | Birmingham | 2020 |
| Birmingham Coldform & Special Fasteners Limited | Wednesbury | 1988 |
| Birmingham Commercial Cooker Ltd | Birmingham | 2020 |
| Birmingham Composite Doors Ltd | Solihull | 2019 |
| Birmingham Defix Chemtek Limited | Beckenham | 2023 |
| Birmingham Education Consultants Limited | Birmingham | 2002 |
| Birmingham Engineering & Repair Solutions Ltd | Sutton Coldfield | 2013 |
| Birmingham Fabrications Limited | Birmingham | 2017 |
| Birmingham Forktrucks Services Ltd | Wolverhampton | 2016 |
| Birmingham Fresh Ltd | Birmingham | 2025 |
| Birmingham Gate Services Limited | Birmingham | 2014 |
| Birmingham GUN Barrel Company, Limited(The) | West Midlands | 1953 |
| Birmingham Halal Abattoir Limited | Birmingham | 2000 |
| Birmingham High Performance Turbomachinery Limited | Birmingham | 2003 |
| Birmingham Hosiery Limited | Birmingham | 1992 |