| Blue Door TOO Limited | Edinburgh | 2016 |
| Blue DOT Psychology Limited | Bristol | 2025 |
| Blue Dove Healthcare Services Ltd | Leicester | 2025 |
| Blue Duck Partners Limited | Bicester | 2022 |
| Blue Eagles Healthcare Limited | Northampton | 2024 |
| Blue Elephant Childcare Ltd | Barnstaple | 2017 |
| Blue Elephant Nursery Limited | Birmingham | 2016 |
| Blue Elsa Ltd | Darlington | 2020 |
| Blue Finch Dental Care Limited | London | 2011 |
| Blue Flamingo Community Hub CIC | Preston | 2024 |
| Blue Fountain Care Limited | Bristol | 2022 |
| Blue GEM Beauty Ltd | Sale | 2024 |
| Blue Giraffe Child Care (Knowle) Ltd | Birmingham | 2013 |
| Blue Glass Therapies Limited | Shrewsbury | 2021 |
| Blue Grass Purple COW Limited | High Peak | 2004 |
| Blue GUM Healthcare Limited | Chesterfield | 2023 |
| Blue Harbour Care Ltd | Ramsgate | 2026 |
| Blue Haven Care Limited | Ipswich | 2018 |
| Blue Health Care Services Ltd | London | 2016 |
| Blue Heart Care Limited | London | 2026 |
| Blue Hive Services Limited | Bishop'S Stortford | 2022 |
| Blue Horizon (PVT) Limited | Greater Manchester | 2019 |
| Blue Horizon Blood Tests Ltd | Beaworthy | 2026 |
| Blue Horizon Healthcare Recruitment Ltd | Northampton | 2026 |
| Blue Horizon Medical Ltd | Norwich | 2022 |
| Blue Hour Therapy Ltd | London | 2025 |
| Blue Human Project CIC | Stroud | 2024 |
| Blue Independent Social Work Limited | Northwich | 2016 |
| Blue Iris Childcare Limited | Swanley | 2023 |
| Blue Iris Healthcare Ltd | Portsmouth | 2021 |
| Blue Iroko Ltd | Luton | 2021 |
| Blue JAY Healthcare Ltd | Lincoln | 2021 |
| Blue Kangaroo Happy Nursery Ltd | Glasgow | 2016 |
| Blue Kangaroo Nursery Hamilton Ltd | Glasgow | 2025 |
| Blue Kite Children Care Limited | Willenhall | 2022 |
| Blue Knight Living Care Ltd | Watford | 2023 |
| Blue Lagoon Centres Ltd | Polegate | 2017 |
| Blue Lagoon Limited | Scunthorpe | 2013 |
| Blue Lemon Health & Safety Limited | Hailsham | 2013 |
| Blue Light Care Ltd | London | 2022 |
| Blue Light Cleaning and Property Management Services Limited | Bideford | 2023 |
| Blue Light Dental Ltd | London | 2018 |
| Blue Light Medicare Ltd | London | 2020 |
| Blue Light Medics Ltd | Dumfries | 2026 |
| Blue Light Support & Consultancy Ltd | Corby | 2022 |
| Blue Light Trauma Services Ltd. | Sandy | 2013 |
| Blue Light Wellbeing Limited | Henley-In-Arden | 2026 |
| Blue Lily Home Care Limited | Pinner | 2018 |
| Blue Lion Care Limited | London | 2023 |
| Blue Locus Limited | Wembley | 2020 |
| Blue Lotus Collective C.I.C. | Chatham | 2024 |
| Blue Lotus Healthcare Ltd | Milton Keynes | 2020 |
| Blue Lumora Ltd | London | 2026 |
| Blue MAR Limited | London | 2012 |
| Blue Maya Physio Ltd | Newcastle Under Lyme | 2021 |
| Blue Meadow Home Care Ltd | Witney | 2026 |
| Blue Medic Consultancy Limited | Kingston Upon Thames | 2017 |
| Blue Medical Services Ltd | Leeds | 2019 |
| Blue Mental Health Education & Training Ltd. | North Shields | 2020 |
| Blue Merit Limited | Sunderland | 2025 |
| Blue Mile Care Ltd | Bishop Auckland | 2024 |
| Blue Mind Healing CIC | Northallerton | 2025 |
| Blue Monkey Consulting Limited | South Croydon | 2008 |
| Blue Monkey Health Limited | South Croydon | 2024 |
| Blue Moon Care Ltd | Taunton | 2012 |
| Blue Moon Consulting Limited | Solihull | 2021 |
| Blue Moon Health and Wellbeing Limited | Cardiff | 2020 |
| Blue Moon Home Support Services Limited | Rugby | 2021 |
| Blue Morph Limited | Norwich | 2014 |
| Blue Mountain Adventures Limited | Derby | 2020 |
| Blue Mountain Homes Ltd. | Derby | 2002 |
| Blue Nest Ltd | London | 2016 |
| Blue Occean Ltd | Swanscombe | 2018 |
| Blue Ocean Bidco 2 Limited | Clitheroe | 2018 |
| Blue Ocean Chiropractic Limited | Bournemouth | 2003 |
| Blue Opal Limited | Worcester | 2006 |
| Blue Orchard Care Limited | Slough | 2025 |
| Blue Orchid Care Ltd | Rainham | 2023 |
| Blue Orchid Counselling and Consultancy Ltd | Enfield | 2023 |
| Blue Orchid Smiles Ltd | London | 2018 |
| Blue PAW Wellbeing and Trauma Support Limited | Peterborough | 2022 |
| Blue PCN Limited | Taunton | 2022 |
| Blue Peanut Limited | Burnley | 2015 |
| Blue Pear Day Nursery Limited | London | 2015 |
| Blue Pearl Homecare Ltd | Harlow | 2019 |
| Blue Pharma Care Ltd | Bradford | 2024 |
| Blue Phoenix Healthcare Ltd | Tilbury | 2026 |
| Blue Phoenix Supplies Ltd | Coventry | 2025 |
| Blue Popies Care & Support Services Limited | London | 2019 |
| Blue Print Healthcare Ltd | Birmingham | 2025 |
| Blue Puffin Medical Limited | Wareham | 2025 |
| Blue Quartz Ltd | Harrow | 2022 |
| Blue Radiography Services Ltd | Nottingham | 2017 |
| Blue Raven Aesthetics Ltd | Sheerness | 2022 |
| Blue Raven Dental and Facial Cosmetics Ltd | Sheerness | 2019 |
| Blue RAY Healings Ltd | Barnsley | 2023 |
| Blue Riband Reporting Limited | St. Albans | 2015 |
| Blue Ribbon Community Care Ltd | Chester | 2009 |
| Blue Ribbon Healthcare Limited | Warrington | 2016 |
| Blue Ridge Care Ltd | Stanford-Le-Hope | 2026 |