| B.M. Injection Limited | Whitchurch | 1995 |
| B.M. Polyco Limited | Bourne | 1978 |
| B.M.B. Engineers (Newcastle) Limited | Stoke-On-Trent | 1994 |
| B.M.B. Industrial Cabs Limited | Birkenhead | 1999 |
| B.M.C. Competitions Department Limited | Worcester | 2002 |
| B.M.D. Fabrications Ltd. | Moreton-In-Marsh | 2004 |
| B.M.E.C (Consulting) Ltd | Bristol | 2015 |
| B.M.Fashions (U.K.) Limited | Leicester | 1999 |
| B.M.I. Engineering Limited | West Midlands | 1975 |
| B.M.K. Steel Ltd | Magherafelt | 2000 |
| B.M.S. Kitchens & Bedrooms Limited | Market Weighton | 2001 |
| B.M.S.M. Limited | Skipton | 1983 |
| B.M.W. (Boards) Limited | Bristol | 1983 |
| B.M.W. Building Products Limited | Chester Le Street | 1985 |
| B.N. Engineering Limited | Solihull | 2003 |
| B.N.O.S. Meditech Limited | Halstead | 1989 |
| B.O.B. Realisations Limited | Welwyn Garden City | 1985 |
| B.O.B. Stevenson Limited | Birmingham | 2016 |
| B.O.E. (Bowmen of England) Limited | West Midlands | 1995 |
| B.O.M. Light Engineering Limited | Leeds | 1973 |
| B.P. & S.C. Limited | Gloucester | 1979 |
| B.P. Frames Ltd | Bristol | 1998 |
| B.P.F. Plant Limited | Annacloy | 1986 |
| B.P.M. Engineering Limited | Swansea | 2005 |
| B.P.S. Holdings Limited | Gloucester | 2003 |
| B.P.S. Security Installation Limited | Harlow | 2006 |
| B.P.Y. Plastic Mouldings Limited | Woodstock | 2020 |
| B.P.Y. Plastics Limited | Woodstock | 2001 |
| B.Print & Display Limited | Newcastle Upon Tyne | 1981 |
| B.R. Engineering Limited | Halesowen | 1998 |
| B.R. Plant Engineers Ltd | Derby | 1986 |
| B.R.A.I Limited | Dagenham | 2022 |
| B.R.Commercials-Uk Limited | Sawbridgeworth | 2012 |
| B.R.E. Limited | Broughty Ferry | 1987 |
| B.Ryan Air Tech Ltd | Manchester | 2016 |
| B.S. Ashley Limited | Walsall | 1976 |
| B.S. Attwall & Co. Limited | Leicester | 1964 |
| B.S. Engineering Ltd. | Nottingham | 1989 |
| B.S. Labels Limited | Earl Shilton | 1983 |
| B.S. Motors Limited | Birmingham | 1994 |
| B.S. Plastics Limited | Birmingham | 2014 |
| B.S. Project Engineering Limited | Northants | 1995 |
| B.S. Steels Limited | Fareham | 1995 |
| B.S. Supplies (Stoke-On-Trent) Limited | Brackley | 2001 |
| B.S. Teasdale & SON Limited | Mexborough | 1998 |
| B.S.B. (Sound) Limited | Market Drayton | 2006 |
| B.S.B. Engineering Services Limited | Sittingbourne, | 1980 |
| B.S.B. Sheet Metal Services Limited | Solihull | 2008 |
| B.S.Components Limited | Leicester | 1983 |
| B.S.N.T. Ltd. | Manchester | 2020 |
| B.S.T. Supplies & Co Ltd | Bushbury | 1978 |
| B.Stossel Limited | Edgware | 1953 |
| B.T. Properties Limited | Oldham | 1983 |
| B.T. Refrigeration Limited | West Yorkshire | 2003 |
| B.T. Repairs & Services Limited | West Bridgford | 2020 |
| B.T. Technical Systems Limited | Oldham | 1972 |
| B.T.C Builders and Contractors Ltd | Dunstable | 2025 |
| B.T.F. Polymers Limited | Shrewsbury | 2004 |
| B.T.M. Print Limited | Watford | 1997 |
| B.V. (Bellvano) Atelier Ltd | Aylesbury | 2025 |
| B.V.A. Tools & Plastics Limited | Batley | 2001 |
| B.V.M. Limited | Southampton | 1988 |
| B.W Engineering (SW) Ltd | Kingsbridge | 2026 |
| B.W Engineering (UK) Ltd | Ashbourne | 2013 |
| B.W. Controls Limited | Wellington | 1987 |
| B.W. Plastics Limited | Essington | 1977 |
| B.W. Systems Limited | Northamptonshire | 1998 |
| B.W.Industries Ltd | Bridlington | 1974 |
| B.W.Mitchinson Limited | | 1971 |
| B.W.P. Spark Plug Manufacturing Company Limited | Pembrokeshire | 2007 |
| B.X.Genpharma Ltd | London | 2024 |
| B.Y. (Simulated Furs) Limited | London | 1973 |
| B.Y.T. Electrical Services Limited | Leicester | 2003 |
| B.Z Transport Ltd | Northampton | 2021 |
| B03B Ltd | Chester | 2020 |
| B1 Aviation Ltd | Leeds | 2024 |
| B1 Design Ltd | Manchester | 2022 |
| B1 Masta Tech Ltd | Woking | 2023 |
| B1 Poultry Limited | Bradford | 2013 |
| B1 Relay Limited | Bristol | 2021 |
| B10 Bakery Ltd | Birmingham | 2025 |
| B19TWY Holdings Ltd | Market Harborough | 2023 |
| B1LLYK0R3A Ltd | London | 2025 |
| B2 Automotive Components Limited | Birmingham | 2002 |
| B2 Engineering Solutions Ltd | Carrickfergus | 2016 |
| B2 Fitness (UK) Limited | Bury | 2007 |
| B2 Heli-Services Ltd | Lytham St. Annes | 2021 |
| B2 Welding Co. Ltd | Rugeley | 2023 |
| B2&B1 Management Ltd | Bishop'S Stortford | 2025 |
| B24DESIGNS Limited | Port Talbot | 2025 |
| B2B (Leicester) Ltd | Leicester | 2024 |
| B2B Cloud Solutions Ltd | Buckinghamshire | 2020 |
| B2B Duplication Limited | Belvedere | 2014 |
| B2B Embroidery & Print Limited | Bolton | 2022 |
| B2B Graphics Ltd | Rushden | 2025 |
| B2B Injection Moulding Ltd | Gateshead | 2019 |
| B2B Inspired Ltd | Newcastle Upon Tyne | 2019 |
| B2B Workwear & Janitorial Limited | Bolton | 2020 |
| B2B1 Print Solutions Limited | Stockport | 2001 |
| B2CONSTRUCTION Ltd | Coventry | 2023 |