| Bloww Hair and Beauty Ltd | Doncaster | 2013 |
| Blox-Org Ltd | Bristol | 2025 |
| Bloxham Computers Ltd | Banbury | 2011 |
| Bloxsly Ltd | London | 2025 |
| Bloxwich Nail Bar Ltd | Birmingham | 2024 |
| Bloōme Aesthetics Limited | Maidenhead | 2026 |
| BLP Aesthetics and Beauty Ltd | Keighley | 2026 |
| BLQ Ltd | Cardiff | 2026 |
| Blqdimnd Ltd | Tooting | 2022 |
| BLR Nail Ltd | Bath | 2025 |
| BLR Salon Ltd | Manchester | 2025 |
| BLR. Medical Aesthetics Ltd | Ripon | 2025 |
| Blrt Limited | Lincolnshire | 2002 |
| BLS Recruit Ltd | London | 2011 |
| Blsa. Ltd | Romford | 2024 |
| BLT Consult Ltd | London | 2020 |
| BLT Direct Limited | Ipswich | 2004 |
| BLT Services Ltd | Cranleigh | 2026 |
| Bltng Ltd | Woking | 2014 |
| BLU Barber Ltd | Bexleyheath | 2025 |
| BLU Barbering Limited | Nottingham | 2009 |
| BLU Bell Healthcare Limited | Birmingham | 2008 |
| BLU BLU Ltd | Woodford Bridge | 2022 |
| BLU Consortium Limited | London | 2021 |
| BLU Cumulus Ltd | Poole | 2014 |
| BLU Fisch Limited | Tenterden | 2014 |
| BLU Hair and Beauty Limited | Wetherby | 2004 |
| BLU Hair Limited | Nottingham | 2007 |
| BLU Leisure Ltd | Christchurch | 2004 |
| BLU Lifestyle Photography Limited | Beckenham | 2017 |
| BLU Nuvo Limited | Benfleet | 2015 |
| BLU SHU Productions Limited | Longniddry | 2002 |
| BLU Window Cleaning Chester UK Ltd | London | 2025 |
| BLU YNK Ltd | Gravesend | 2023 |
| Blu-Gates Limited | West Drayton | 2011 |
| BLU3PR1N7 Limited | Brighton | 2018 |
| Blubelle Beauté Ltd | Bury St. Edmunds | 2024 |
| Bluberry Marketing Ltd | Carluke | 2018 |
| Blucher Limited | Doncaster | 2006 |
| Bluclinics London Ltd | Feltham | 2025 |
| Blue & Green Limited | | 1999 |
| Blue 365 Limited | Nottingham | 2023 |
| Blue Aegean Limited | London | 2015 |
| Blue Alterations and DRY Cleaners Ltd | London | 2022 |
| Blue Anchor Toilets Community Interest Company | Minehead | 2016 |
| Blue and Red Ventures Ltd | London | 2020 |
| Blue and White Knights Limited | Ulverston | 2023 |
| Blue Angels Motorcycle Club Ltd | Belfast | 2022 |
| Blue Aquariums Design Limited | London | 2018 |
| Blue ARC Constructions Limited | Hayes | 2019 |
| Blue Arch Limited | London | 2024 |
| Blue Arrow Leadership Limited | Wrexham | 2024 |
| Blue Ashton Resources Ltd | Morley | 2019 |
| Blue Audio Ltd. | Lanark | 2016 |
| Blue Badge Index CIC | Bexleyheath | 2026 |
| Blue Baltic Entertainment Limited | Wincanton | 1989 |
| Blue Banana Events Limited | Silsoe | 2021 |
| Blue Barber Shop Limited | Liverpool | 2004 |
| Blue Bay Events Ltd | Bournemouth | 2012 |
| Blue Bay Interior Fit OUT Consultancy Ltd | London | 2018 |
| Blue Bear Bill INK Ltd | Saxmundham | 2022 |
| Blue Bear Conco Limited | Milton Keynes, Northamptonshire | 2023 |
| Blue Bear Prints Ltd | London | 2026 |
| Blue Beauty Limited | London | 2007 |
| Blue BEE Customs Limited | Stockport | 2021 |
| Blue Beech Limited | Leeds | 2020 |
| Blue Begonia Ltd | Weybridge | 2017 |
| Blue Bell Drycleaners Ltd | Amersham | 2021 |
| Blue Bell Spa UK Ltd | Hull | 2026 |
| Blue Beret Charitable Trust | Barnsley | 2021 |
| Blue Bert Parsonage Limited | Maidstone | 2016 |
| Blue Bird Bedford Limited | Sandown | 2014 |
| Blue Bird Hair Lounge Ltd | Maidstone | 2026 |
| Blue Black Ltd | London | 2024 |
| Blue Bond Limited | Doncaster | 2021 |
| Blue Boston Limited | Bristol | 2023 |
| Blue Box Property Maintenance Ltd | Kettering | 2015 |
| Blue Box Storage (Doncaster) Ltd | Doncaster | 2013 |
| Blue Box Storage (Sheffield) Limited | Sheffield | 2023 |
| Blue Bridge Facility Management Ltd | Manchester | 2023 |
| Blue Bridge Ltd | Belfast | 2008 |
| Blue Brolly (UK) Ltd | London | 2012 |
| Blue Bubble D & L Limited | London | 2011 |
| Blue Bubbles Launderette Ltd | Stockport | 2006 |
| Blue Building Environmental Organisation Ltd | Perth | 2021 |
| Blue Butterfly Gardens Ltd | Waltham Abbey | 2019 |
| Blue Candles Support Limited | London | 2025 |
| Blue Castle Limited | London | 2025 |
| Blue Castle Utilities Ltd | Grantham | 2022 |
| Blue Castor Limited | Pinner | 2017 |
| Blue Cat Tattoo Studios Limited | Southampton | 2026 |
| Blue Chart Limited | London | 2024 |
| Blue Checker Limited | Edinburgh | 2012 |
| Blue Chilli Events Hire Ltd | Romford | 2023 |
| Blue Chip Cleaning & Support Services Ltd | Borehamwood | 2011 |
| Blue Chip Event Security Ltd | Essex | 2019 |
| Blue Circle Events Limited | Crawley | 2023 |
| Blue Cloud Aviation Limited | Weybridge | 2024 |
| Blue Coast Laundry Ltd | Bournemouth | 2025 |
| Blue Collar Conservatism Ltd | Preston | 2012 |