| BIT Remit Ltd | Manchester | 2025 |
| BIT Testing Limited | Solihull | 2013 |
| Bita Holdings Limited | Richmond | 2022 |
| Bita's Mortgage Services Ltd | Leeds | 2018 |
| Bitanah Ltd | London | 2022 |
| Bitazza Trade Ltd | London | 2025 |
| Bitbankers Investment Ltd | Cardiff | 2024 |
| Bitblue Limited | Newton Abbot | 2014 |
| Bitblue Nova Ltd | London | 2026 |
| Bitbots Ltd | Romford | 2018 |
| Bitcashier Ltd | London | 2020 |
| Bitcoin Banque Ltd | Cardiff | 2019 |
| Bitcoin Global Capital Limited | High Wycombe | 2015 |
| Bitcoin SV Ltd | Hoddesdon | 2019 |
| Bitcore Ltd | Aldershot | 2025 |
| Bitdu Limited | Cardiff | 2020 |
| Bite Fast Exchange Ltd | London | 2025 |
| Bite Polen Wealth Management Limited | London | 2024 |
| Bite Polen WM (UK) Limited | London | 2025 |
| Bitetech Infrastructure Ltd | Coulsdon | 2026 |
| Bitfifty Ltd | London | 2020 |
| Bitgo Holdings Emea, Ltd | London | 2019 |
| Bitheim Global Limited | Cambridge | 2025 |
| Bithell Asset Finance Solutions Ltd | Dumfries | 2014 |
| Bithell Davies Funding Solutions Limited | Dumfries | 2024 |
| Bithold Ltd | Cardiff | 2021 |
| Bitins Limited | London | 2015 |
| Bitiqi Holdings Limited | London | 2025 |
| Bitklean Ltd | Stoke-On-Trent | 2025 |
| Bitmacs Group Limited | London | 2025 |
| Bitmap Capital Limited | London | 2025 |
| Bitopia Ltd | Cardiff | 2018 |
| Bitover Limited | London | 1974 |
| Bitpanda UK Holding Ltd. | London | 2023 |
| Bitpointai Ltd | Slough | 2018 |
| Bitr Holdings Limited | Ullenhall | 2012 |
| Bitrade Ltd | Cardiff | 2020 |
| Bitradecoin Ltd | London | 2025 |
| Bitradex Fintech Limited | Bury St. Edmunds | 2025 |
| Bitshine Capital Ltd | London | 2021 |
| Bitstack Crowd Limited | Exeter | 2026 |
| Bitstamp Limited | London | 2012 |
| Bitstamp UK Ltd | London | 2022 |
| Bitstrategy Ltd | Taunton | 2025 |
| Bitterley Underwriting Limited | London | 1998 |
| Bittersweet Mortgages Ltd | Wolverhampton | 2024 |
| Bittrex Global (UK) Limited | Altrincham | 2022 |
| Bitwallet Limited | London | 2018 |
| Bitwise Europe Management Ltd. | London | 2019 |
| Bivi Limited | London | 2019 |
| Bivillas Limited | Christchurch | 2014 |
| Biwa Investments Ltd | London | 2022 |
| Bixbio Limited | London | 2021 |
| Bixx Limited | Woodford Green | 2020 |
| Biysa Limited | Grimsby | 2026 |
| Biyyanii Capital Holdings Ltd | Leamington Spa | 2026 |
| BIZ Bank Ltd | Stamnore | 2004 |
| BIZ Loans 4U Limited | Liverpool | 2016 |
| BIZ Loans Engine Limited | Barkingside | 2019 |
| BIZ Safety Ltd | Wallington | 2021 |
| Biz-Works UK Ltd | Worthing | 2005 |
| Bizaroux Consulting & Growth Ltd | Birmingham | 2025 |
| Bizarre Holdings Limited | Greater Manchester | 2020 |
| Bizbell Ventures Limited | London | 2022 |
| Bizbritain Finance Limited | London | 2013 |
| Bizfi Limited | Rotherham | 2025 |
| Bizfirst Ltd | Coventry | 2019 |
| Bizflow Limited | Blackpool | 2026 |
| Bizim Group Limited | London | 2025 |
| Bizkit-Tin Ltd | Dorchester | 2023 |
| Bizl Limited | London | 2017 |
| Bizlife Protect Ltd | Northampton | 2024 |
| Biznav Group Limited | Bromley | 2018 |
| Biznet Solutions Ltd | Birmingham | 2026 |
| Biznet Utilities Ltd | Birmingham | 2025 |
| Bizota Ltd | Dartford | 2024 |
| Biztech International Holdings Ltd | London | 2021 |
| Bizvic Financial Services Ltd | Coventry | 2020 |
| Bizz Corp Capital Ltd | Margate | 2025 |
| BIZZY25 Holdings Limited | Northampton | 2019 |
| BJ & JJ Group Ltd | Plymouth | 2022 |
| BJ & JJ Investments Ltd | Plymouth | 2017 |
| BJ Aylward Ltd | London | 2020 |
| BJ Cheese (Holdings) Limited | Smethwick | 2016 |
| BJ Cheese Group Limited | Smethwick | 2024 |
| BJ Ghuman Holdings Limited | Birmingham | 2022 |
| BJ Hayes Ltd | Lincoln | 2018 |
| BJ Security Limited | Ruislip, | 2025 |
| BJ054 Limited | London | 2025 |
| BJA Investments Limited | Pulborough | 2014 |
| BJA Ltd | King'S Lynn | 2022 |
| BJC Care Limited | Bolton | 2020 |
| BJD Financial Services Limited | Hoylake | 2022 |
| BJD Investments Ltd | Rochester | 2019 |
| Bjd.Global Limited | Lytham St. Annes | 2021 |
| Bjerregaard Holdings Limited | Beaconsfield | 2021 |
| Bjew Holdings Limited | Derby | 2025 |
| BJF Organisation Limited | Maidstone | 2011 |
| Bjfm Limited | Stockton-On-Tees | 2002 |
| BJG Priory Ltd | Colchester | 2023 |