| Black Sheep Shepherd Huts Ltd | Loughton | 2018 |
| Black Sheep Transitions Limited | Chester | 2018 |
| Black Shuck Ltd | Fakenham | 2015 |
| Black Skip Machinery Ltd | Ipswich | 2024 |
| Black Solutions Ltd | Armagh | 2013 |
| Black Squirrel Distillery Ltd | Southend-On-Sea | 2019 |
| Black Stag Drinks Ltd | London | 2026 |
| Black Star Diva Ltd | Birmingham | 2020 |
| Black Star Motorsport Ltd | Leeds | 2022 |
| Black Star Orbiter(Uk) Limited | London | 2017 |
| Black Steel Doors Ltd | London | 2018 |
| Black Sun Brewery Ltd | Fleet | 2023 |
| Black Sun Studios Ltd | Romford | 2020 |
| Black Swallow Productions Ltd | Sherrington | 2018 |
| Black Swan Furniture Ltd | Dunmow | 2019 |
| Black Swan Marine Services Ltd | Nottingham | 2022 |
| Black Swan Printers (Dawlish) Ltd | Dawlish | 2005 |
| Black T Stage Building Limited | Tonbridge | 2025 |
| Black T Stage Engineering PLC | Tonbridge | 2026 |
| Black TAR Brewing Co Ltd | Swansea | 2025 |
| Black Taxi Repairs Ltd | London | 2014 |
| Black Teknigas & Electro Controls Ltd. | St Neots | 2001 |
| Black Timber Services Ltd | London | 2025 |
| Black to White Electrical Wholesalers Limited | Hayes | 2020 |
| Black Top Performance Engineering Ltd | Heywood | 2019 |
| Black TOR Brewery Ltd | Salisbury | 2013 |
| Black Triangle Solution Limited | Southampton | 2015 |
| Black Tulip Retail Ltd | Harrow | 2023 |
| Black VEN Distillery Limited | Frome | 2019 |
| Black Wildcat Ltd | Christchurch | 2010 |
| Black Wolf Brewery Limited | Glasgow | 2014 |
| Black Wolf Coffee Company Ltd | Manchester | 2021 |
| Black Wolf Limited | St. Neots | 2012 |
| Black Yeti Coffee Co Ltd | Ledbury | 2025 |
| Black&Greyclothing Limited | Blackburn | 2023 |
| Black's Pies Limited | Wrexham | 2017 |
| Blacka Acoustics Limited | Whitchurch | 2000 |
| Blackayard Studio Limited | Manchester | 2022 |
| Blackbear Essex Limited | Canvey Island | 2018 |
| Blackbeard Marine Ltd | Fareham | 2023 |
| Blackberet Media Limited | Chesham | 2023 |
| Blackbird Bakery Limited | London | 2006 |
| Blackbird Books Ltd | Helston | 2024 |
| Blackbird Brewing Ltd | Burgess Hill | 2020 |
| Blackbird Industries Ltd | Lichfield | 2019 |
| Blackbird Performance Ltd | Birmingham | 2025 |
| Blackbirdbox Consultancy Ltd | Eastbourne | 2026 |
| Blackboards Europe Limited | Penzance | 2011 |
| Blackbox Logistix Ltd | London | 2024 |
| Blackbox Products Ltd | Ilminster | 2024 |
| Blackbox-Av Ltd | Port Talbot | 2010 |
| Blackbridge Corporation Ltd | Cambridge | 2024 |
| Blackbull Lighting Ltd | London | 2026 |
| Blackburn & Co Ltd | Bury St. Edmunds | 2014 |
| Blackburn & Ribble Window Frames Limited | Blackburn | 2020 |
| Blackburn & Roberts Manufacturing Ltd | Manchester | 2014 |
| Blackburn Bailey Group Limited | Southend-On-Sea | 2001 |
| Blackburn Caravan Services Ltd | Blackburn | 2019 |
| Blackburn Chemicals Limited | Blackburn | 1973 |
| Blackburn Circuit Design Holdings Limited | Oldham | 2011 |
| Blackburn Circuit Design Limited | Oldham | 1990 |
| Blackburn Conveyor Services Limited | Elland | 2009 |
| Blackburn Distributions Ltd. | Burnley | 2022 |
| Blackburn Pallets Limited | Darwen | 1992 |
| Blackburn Power Limited | Preston | 2009 |
| Blackburn Print Limited | Hove | 1974 |
| Blackburn Starling & Company Limited | | 1987 |
| Blackburn Trailers Limited | Chichester | 1998 |
| Blackburn Welding Services Ltd | Blackburn | 2021 |
| Blackburn Windows Limited | Blackburn | 2024 |
| Blackburne Motorcycles Ltd | Swaffham | 2024 |
| Blackburns the Bakers Ltd | Rochdale | 2025 |
| Blackcat Upcyclers Limited | Glasgow | 2023 |
| Blackcore Technologies Ltd | Bristol | 2023 |
| Blackcraig Limited | Blairgowrie | 2020 |
| Blackcurrant Babies Limited | Hemel Hempstead | 2014 |
| Blackcurrant Global Limited | Oldham | 2014 |
| Blackdog Digital Print Limited | Barnet | 2010 |
| Blackdog Games Ltd | Hertford | 2011 |
| Blackdog Print Limited | Barnet | 2018 |
| Blackdog Welding Ltd | Robertsbridge | 2023 |
| Blackdown Buildings Limited | Cullompton | 2012 |
| Blackdown Fabrication Limited | London | 2023 |
| Blackdown Fernhurst Ltd | Fernhurst | 2010 |
| Blackdown Precision Tables Ltd | London | 2026 |
| Blackdown Shepherd Huts Ltd. | Ilminster | 2011 |
| Blackdrop Cosmetics Ltd | Leigh | 2025 |
| Blackdyke Engineers Limited | Carlisle | 1966 |
| Blackedge Brewing Company Ltd | Bolton | 2009 |
| Blackened Sun Brewing Company Limited | Milton Keynes | 2017 |
| Blackened Sun Productions Ltd | Clacton-On-Sea | 2023 |
| Blacker Sheep Limited | Launceston | 2005 |
| Blacker Steel Fabrications Limited | York | 2003 |
| Blacker Watches Ltd | Aylesbury | 2023 |
| Blackett Rail Limited | Gateshead | 2025 |
| Blackfang Ltd | Glasgow | 2024 |
| Blackfield Mechanical Engineering Limited | Chandlers Ford | 2008 |
| Blackfields Furniture Ltd | Bristol | 2014 |
| Blackfinger Coffee Roasters Ltd | London | 2025 |
| Blackfire Food Ltd | Belfast | 2021 |