| Blue Coast Wealth Management Limited | Colchester | 2016 |
| Blue Cocktail Group (Holdings) Limited | Manchester | 2024 |
| Blue Collar Group Ltd | Oxford | 2021 |
| Blue Consultants Limited | Leeds | 2017 |
| Blue Consulting Services Ltd | Didsbury | 2019 |
| Blue Coys Capital Limited | Chelmsford | 2022 |
| Blue Crest PTY Ltd | Basingstoke | 2011 |
| Blue Crocodile Money Ltd | Morley | 2019 |
| Blue Cross Helpline Ltd | Bolton | 2019 |
| Blue Crown Holdings Ltd | Newton Abbot | 2024 |
| Blue Crystal Property Management Ltd | Norwich | 2022 |
| Blue Cube Systems Ltd | London | 2024 |
| Blue Cubed Holdings Limited | Oxford | 2022 |
| Blue Dawn EOT Limited | Birmingham | 2020 |
| Blue Day Capital Ltd | Edgware | 2013 |
| Blue Day Ventures Ltd | Chessington | 2025 |
| Blue Deer Partners Ltd | London | 2025 |
| Blue Diamond Consultancy Limited | Glasgow | 2014 |
| Blue Diamond Sports Limited | London | 2018 |
| Blue Diamonds Limited | Wembley | 2006 |
| Blue Dolphin Capital Ltd | Dorchester | 2025 |
| Blue Dolphin Health Ltd | London | 2025 |
| Blue Door Funding Limited | Welwyn Garden City | 2025 |
| Blue Door Holdings Group Limited | Brighton | 2024 |
| Blue Doors Holdings Ltd | London | 2025 |
| Blue Doors Investments Ltd | London | 2021 |
| Blue Dorsal Properties Limited | Brighton | 2020 |
| Blue DOT Holdings Limited | Chandler'S Ford | 2018 |
| Blue Dragon Finance Ltd | Penarth | 2014 |
| Blue Earth Capital (UK) Ltd | London | 2022 |
| Blue Earth Investments Limited | St. Austell | 2025 |
| Blue Emerald Group Ltd | Cannock | 2024 |
| Blue Energy Logistics Limited | Norwich | 2020 |
| Blue Energy PV Holdings Limited | Alderley Edge | 2011 |
| Blue Energy Wind (Nominee) Limited | Alderley Edge | 2021 |
| Blue Finance Limited | London | 2018 |
| Blue Fish Mortgage Solutions Limited | Glasgow | 2022 |
| Blue Fish Partnership Limited | Redditch | 2009 |
| Blue Flamingo Holdings Ltd | Surbiton | 2025 |
| Blue Fort Holdings Ltd | Birmingham | 2023 |
| Blue FOX Financial Ltd | London | 2018 |
| Blue FOX Wealth Management Limited | Yeovil | 2014 |
| Blue Freedom Ltd | London | 2022 |
| Blue Frog Finance Limited | Potters Bar | 2017 |
| Blue GEM Holdings Limited | Brentwood | 2023 |
| Blue GEM Management Services Limited | Brentwood | 2023 |
| Blue Glacier II UK Holdings Ltd | London | 2023 |
| Blue Gold Holdings Limited | London | 2023 |
| Blue Goldstone Holdco Limited | Worthing | 2021 |
| Blue Goldstone Topco Limited | Worthing | 2021 |
| Blue Gower 2 Limited | Poole | 2022 |
| Blue Grey Ltd | Launceston | 2021 |
| Blue Group Holdings Ltd | London | 2018 |
| Blue Group Services Limited | Keele | 2020 |
| Blue Guardian Holding Ltd | London | 2021 |
| Blue Gull Holdings Limited | Letherhead | 2021 |
| Blue Harbor Capital Ltd | London | 2025 |
| Blue Harbour Estates Holdings Limited | Gillingham | 2022 |
| Blue Haven Assets Limited | Billericay | 2022 |
| Blue Hawk Holdings Limited | Cambridge | 2025 |
| Blue Heron Financial Services Limited | London | 2019 |
| Blue Heron Holdings Ltd | Taunton | 2018 |
| Blue Heron Property Limited | London | 2023 |
| Blue Herring Mortgage & Protection Services Ltd | Wellingborough | 2020 |
| Blue Hippo Consulting Limited | Southport | 2024 |
| Blue HK Investments Ltd | Warwick | 2010 |
| Blue Holdco Limited | Reading | 2018 |
| Blue Horizon 2 Limited | Leicester | 2020 |
| Blue Horizon Asset Management Limited | London | 2011 |
| Blue Horizon Asset Management Nominees Limited | London | 2022 |
| Blue Horizon Bidco Limited | London | 2025 |
| Blue Horizon Equities Limited | Slough | 2024 |
| Blue Horizon Group Holdings Limited | Bury St Edmunds | 2025 |
| Blue Horizon Investco UK Ltd | London | 2026 |
| Blue Horizons (Family Investment) Limited | Oswestry | 2023 |
| Blue Horn Holdings Ltd | Romford | 2022 |
| Blue Horseshoe Enterprises Ltd | Sevenoaks | 2022 |
| Blue House Project Limited | Chichester | 2020 |
| Blue Hyde Limited | London | 2025 |
| Blue I Group Limited | Leeds | 2016 |
| Blue I Holdings Limited | Leeds | 2022 |
| Blue Indemnity Brokers Limited | Birmingham | 2025 |
| Blue International Holdings Limited | London | 2017 |
| Blue Investment Group Limited | London | 2025 |
| Blue Investment Holdings Ltd | London | 2020 |
| Blue Iris Bidco Limited | London | 2024 |
| Blue Iris Midco Limited | London | 2024 |
| Blue Iris Topco Limited | London | 2024 |
| Blue John Services Limited | Liss | 2024 |
| Blue Jupiter Limited | Whitchurch | 2007 |
| Blue Kite Group Ltd | Leeds | 2023 |
| Blue Koala Limited | London | 2019 |
| Blue Label Wealth Management Limited | Poole | 2015 |
| Blue Labrador Limited | Kendal | 2021 |
| Blue Lagoon Estates Ltd | Pontefract | 2019 |
| Blue Lake Syndicate Ltd | London | 2024 |
| Blue Leaves Financial Management Ltd | London | 2011 |
| Blue Light Dent Holding Ltd | Altrincham | 2019 |
| Blue Light Group Ltd | London | 2019 |
| Blue Light Holdings Limited | London | 2007 |