| Big Glasses Limited | Exeter | 2023 |
| Big Gold Crown Limited | Willenhall | 2023 |
| Big Grass Investments Ltd | Ascot | 2024 |
| Big Green Coach Holding Limited | Birmingham | 2026 |
| Big Green DOT Ltd | London | 2018 |
| Big Green Light Ltd | London | 2019 |
| Big Help Ethical Financial Services Limited | Liverpool | 2021 |
| Big Hippo Investments Ltd | Malmesbury | 2023 |
| Big Holder Ltd | London | 2024 |
| Big Huge Money Ltd | London | 2022 |
| Big in Business Ltd | Torquay | 2024 |
| Big Investment One Limited | Willenhall | 2017 |
| Big Issue Access Limited | London | 2016 |
| Big Issue Invest Corporate Social Venturing Ltd | London | 2013 |
| Big Issue Invest Fund Management Ltd | London | 2013 |
| Big Issue Invest Limited | London | 2003 |
| Big Issue Social Investments Limited | London | 2009 |
| Big Jelly Buildings Limited | Ramsgate | 2016 |
| Big K (Holdings) Limited | Tottenham Hale | 1990 |
| Big MAN Investments Limited | Shrewsbury | 2019 |
| Big Mosside Limited | Ayr | 2023 |
| Big Mountain Brew House Limited | London | 2022 |
| Big MV Limited | London | 2020 |
| Big Nominee Co Limited | London | 2025 |
| Big Orbital Holdco Limited | London | 2026 |
| Big Pencil Limited | Petworth | 2026 |
| Big Picture Care Group Ltd | Plymouth | 2023 |
| Big Picture Equity Ltd | Huddersfield | 2025 |
| Big Picture Financial Planning Ltd | Sheffield | 2020 |
| Big Picture Wealth Planning Ltd | Epsom | 2017 |
| Big Planet Ventures Ltd | London | 2019 |
| Big Purple Group Limited | Swalwell | 2022 |
| Big Rainy Street Ltd | Harrow | 2025 |
| Big Red Recruitment Group Limited | Stratford-Upon-Avon | 2020 |
| Big Red Sales (UK) Limited | Cirencester | 2015 |
| Big Red Toolbox Holdings Ltd | Chichester | 2025 |
| Big Rock Property Investment Limited | Enfield | 2023 |
| Big Saffron Holding Limited | London | 2026 |
| Big School Capital Ltd | Poole | 2022 |
| Big Secret Investment Limited | London | 2018 |
| Big Seedd Limited | London | 2025 |
| Big Sister & the Holding Company Ltd | Hove | 2019 |
| Big Skies Wealth Management Limited | Ipswich | 2016 |
| Big Sky Capital Limited | London | 2026 |
| Big Sky Holdings Ltd | Sudbury | 2025 |
| Big Sour Ltd | London | 2025 |
| Big Stone Holdings Limited | Cheltenham | 2023 |
| Big Swift Limited | Watford | 2022 |
| Big T Fitness Limited | Norwich | 2022 |
| Big T Ltd | Poole | 2025 |
| Big Teapot Ltd | Liverpool | 2019 |
| Big Think Capital UK Limited | London | 2026 |
| Big Think Holdings Limited | Glasgow | 2023 |
| Big Thunder Ltd | Leek | 2018 |
| Big Ticket Asset Finance Limited | Brackley | 2022 |
| Big TIM Holdings Limited | Bristol | 2017 |
| Big Time Fact Limited | London | 2018 |
| Big Time Holdings Limited | London | 2024 |
| Big Tree Holdco Ltd | Iver | 2024 |
| Big Tree Holdings Ltd | Iver | 2021 |
| Big Van World Holdings Limited | Witney | 2023 |
| Big Warranties Limited | Poole | 2009 |
| Big Wave Whiskey Limited | London | 2023 |
| Big Yellow Nominee NO. 1 Limited | Bagshot | 2007 |
| Big Yellow Nominee NO.2 Limited | Bagshot | 2007 |
| Big Yellow Self Storage Company 1 Limited | Surrey | 2002 |
| Big Yellow Self Storage Company 2 Limited | Bagshot | 2003 |
| Big Yellow Self Storage Company 3 Limited | Bagshot | 2003 |
| Big Yellow Self Storage Company 4 Limited | Surrey | 1999 |
| Big Zebra Capital Limited | Preston | 2024 |
| Big ZEE Holding Company Limited | Preston | 2024 |
| Biga Ploutos Ltd | London | 2021 |
| Bigaloo Ltd | Cardiff | 2004 |
| Bigban AS Ltd | London | 2025 |
| Bigbang Hair Ltd | Edinburgh | 2014 |
| Bigbudbama Limited | Deeside | 2025 |
| Bigchange Bidco Limited | Reading | 2021 |
| Bigchange Midco Limited | Reading | 2021 |
| Bigchange Topco Limited | Reading | 2021 |
| Bigcity London Ltd | London | 2018 |
| Bigday Designs Holdings Limited | Peterborough | 2018 |
| Bigdeal Cleaning Ltd | London | 2025 |
| Bigfire Holdings Limited | Exeter | 2017 |
| Bigfoot Operations Limited | London | 2024 |
| Bigfrith Investments | Maidenhead | 2014 |
| Biggar Financial Planning Limited | Hemel Hempstead | 2010 |
| Bigger Enterprises Limited | London | 2020 |
| Bigger Peach Limited | London | 2006 |
| Bigger Perspective UK Limited | London | 2024 |
| Bigger Picture Holdings Limited | London | 2025 |
| Biggie Group Limited | London | 2019 |
| Biggie Holdings Ltd | London | 2021 |
| Biggleswade Holdco Limited | Rugby | 2023 |
| Biggleswade Sheet Metal Limited | Milton Keynes | 2025 |
| Biggos Limited | Mold | 2021 |
| Bighand UK Bidco Limited | London | 2020 |
| Bighand UK Holdco Limited | London | 2020 |
| Bighand UK Midco Limited | London | 2020 |
| Bighand UK Topco Limited | London | 2020 |
| Bighead Fasteners Limited | Verwood | 2014 |