| Big Country Trading Limited | Dunfermline | 2021 |
| Big COW Sports Ltd | Milton Keynes | 2013 |
| Big COX Productions Ltd | Droitwich | 2014 |
| Big Creative Limited | Bexley | 2024 |
| Big Culture Music Ltd | Poole | 2016 |
| Big Day Pro Live Ltd | Neath | 2023 |
| Big Deal Films Limited | Iver | 2014 |
| Big Design Corporation Limited | Newquay | 1999 |
| Big Difference Company Limited | | 1995 |
| Big Difference Productions Limited | Leicester | 2011 |
| Big Disco Limited | Wolverhampton | 2002 |
| Big Dog Competitions & Giveaways Ltd | Stoke-On-Trent | 2026 |
| Big Dog Events Limited | Chichester | 2025 |
| Big Dog Little Dog Limited | Alton | 2016 |
| Big Drag Events Ltd | Manchester | 2024 |
| Big Dreamer Productions Ltd | Cardiff | 2017 |
| Big Drums Limited | Braintree | 2021 |
| Big Ears Music and Design Ltd | Sheffield | 2007 |
| Big Factotum Limited | London | 2014 |
| Big Fang Bristol Ltd | Liverpool | 2018 |
| Big Fang Cardiff Ltd | Liverpool | 2018 |
| Big Fang Glasgow Ltd | Liverpool | 2018 |
| Big Fang Liverpool Ltd | Liverpool | 2016 |
| Big Fang London Ltd | Liverpool | 2018 |
| Big Fang Newcastle Ltd | Liverpool | 2018 |
| Big Fang Nottingham Ltd | Liverpool | 2018 |
| Big Fang Sheffield Ltd | Liverpool | 2018 |
| Big Fang Stratford Limited | Liverpool | 2024 |
| Big FAT Jenna Ltd | Manchester | 2024 |
| Big Feast Ltd | London | 2025 |
| Big Finish Drama Limited | Maidenhead | 2025 |
| Big Finish Entertainment Limited | Maidenhead | 2014 |
| Big Finish Media Group Limited | Maidenhead | 2015 |
| Big Finish Merchandise Limited | Maidenhead | 2020 |
| Big Finish Theatre Limited | Maidenhead | 2015 |
| Big Fish Advantage Limited | Harlow | 2025 |
| Big Fish Creative Limited | Luton | 1999 |
| Big Fish Darts Ltd | Windermere | 2025 |
| Big Fish Enterprises Ltd. | Cambridge | 2008 |
| Big Fish Little Fish Productions Limited | London | 2015 |
| Big Fish Music Partnerships Limited | London | 1999 |
| Big Fish Records Ltd | Cardiff | 2023 |
| Big Foot Events Limited | Blackpool | 2005 |
| Big Foot Music Management Ltd | London | 2015 |
| Big Foot Productions Limited | 41 Stamford Hill | 1989 |
| Big Framed Shapes Ltd | Harrow | 2020 |
| Big Fridge London CIC | London | 2026 |
| Big Friendly Graphic Production Limited | Faversham | 2017 |
| Big G Productions Limited | Sevenoaks | 1983 |
| Big G'S Health and Fitness Ltd | Bolton | 2015 |
| Big Ginger TOM Music Limited | Abingdon | 2017 |
| Big Giraffe Events Ltd | Northampton | 2025 |
| Big Gospel Choir Ltd | London | 2024 |
| Big Grandma Energy Ltd | Reading | 2024 |
| Big GUN Graphics Ltd | Horsham | 2015 |
| Big Guns Live Limited | Birmingham | 2014 |
| Big Hair Limited | West Molesey | 2007 |
| Big Hand People Limited | Reigate | 1999 |
| Big Hand Recordings Limited | London | 2009 |
| Big Health & Fitness C.I.C. | Luton | 2015 |
| Big Hearted Marketing Ltd | London | 2016 |
| Big Heritage C.I.C. | Liverpool | 2011 |
| Big Hill Music Limited | London | 2025 |
| Big Hitters Promotions Ltd | Leeds | 2024 |
| Big Horizon Music Limited | London | 2025 |
| Big Hornns Limited | Manchester | 2018 |
| Big House Events Ltd | Edinburgh | 2007 |
| Big Human Theatre Ltd | Banbury | 2014 |
| Big Idea Photography Ltd | Felixstowe | 2015 |
| Big Ideas by the Sea CIC | Scarborough | 2020 |
| Big Ideas Company Limited | Luton | 2015 |
| Big Ideas Product Development Limited | Poole | 1999 |
| Big Image Systems UK Limited | London | 2015 |
| Big in DI Manor Entertainment Ltd | Huddersfield | 2019 |
| Big J BBQ Company Ltd | Halifax | 2025 |
| Big JET TV Live Ltd | London | 2017 |
| Big Joints Ltd | London | 2018 |
| Big Jump Inflatables Ltd | Swaffham | 2023 |
| Big Kahuna Management Limited | Gerrards Cross | 2022 |
| Big KID Entertainment Limited | Crewe | 2005 |
| Big Kids Bounce Ltd | Norwich | 2023 |
| Big Kiss Limited | London | 2012 |
| Big Letter Events Limited | Glasgow | 2016 |
| Big Life Adventures Limited | Broadstone | 2010 |
| Big Little Events Limited | Glasgow | 2023 |
| Big Little FUN Limited | London | 2018 |
| Big Little Productions Ltd | London | 2007 |
| Big Little Theatre School Limited | Wimborne | 2003 |
| Big Live Global Limited | London | 2026 |
| Big Love Music & Arts C.I.C. | Penarth | 2020 |
| Big LOZ Official Ltd | Swindon | 2020 |
| Big MAK Strength Ltd | Wigan | 2025 |
| Big MAN Ventures Ltd | London | 2011 |
| Big Match Temperament Sports Group Ltd | London | 2025 |
| Big MO Entertainment Ltd | Birmingham | 2026 |
| Big Mouth Competitions Limited | Wigan | 2025 |
| Big Mouth Productions Ltd | Saltburn-By-The-Sea | 2013 |
| Big Muscle Limited | Manchester | 2025 |
| Big Music Family Ltd. | London | 2021 |
| Big Nature Limited | Brighton | 2014 |