| Blue Monkey Pubs Limited | Hospitality | 2011 |
| Blue Mountain Products Ltd | Wholesale & retail | 2022 |
| Blue Ocean Residentials Ltd | Real estate | 2018 |
| Blue OWL Properties Ltd | Real estate | 2019 |
| Blue Peak Finance Limited | Financial services | 2024 |
| Blue Pearl Pinxton Ltd. | Hospitality | 2019 |
| Blue Planet Buildings (UK) Limited | Manufacturing | 2011 |
| Blue Property (Group) Limited | Financial services | 2012 |
| Blue Property Investment UK Limited | Real estate | 2007 |
| Blue Property Maintenance UK Limited | Other services | 2007 |
| Blue Property Management UK Limited | Households | 2004 |
| Blue Radiography Services Ltd | Health & social care | 2017 |
| Blue Risk Management UK Limited | Other services | 2007 |
| Blue River Technologies Ltd | Wholesale & retail | 2025 |
| Blue Satin Support Ltd. | Hospitality | 2013 |
| Blue Sierra Limited | Professional & scientific | 2020 |
| Blue Sky Accessories Ltd | Wholesale & retail | 2024 |
| Blue Sky Advertising Limited | Information & communication | 2017 |
| Blue Sky Clothing Limited | Administrative & support | 2014 |
| Blue Sky Commercial Cleaning Limited | Administrative & support | 2020 |
| Blue Sky Communications Limited | Professional & scientific | 2004 |
| Blue Sky Dreams Consultancy Limited | Professional & scientific | 2021 |
| Blue Skyline Properties Ltd | Real estate | 2024 |
| Blue Spark Developments Ltd | Construction | 2015 |
| Blue Spark Electrical Ltd | Construction | 2026 |
| Blue Stamp Holdings Limited | Financial services | 2023 |
| Blue Stamp Travel Limited | Administrative & support | 2018 |
| Blue Star Market Ltd | Wholesale & retail | 2024 |
| Blue Stone Mining LLP | | 2015 |
| Blue Street IT Limited | Information & communication | 2015 |
| Blue Supply Limited | Wholesale & retail | 2022 |
| Blue Volta Ltd | Wholesale & retail | 2025 |
| Blue Wave Security Ltd | Administrative & support | 2021 |
| Blue Wicket Ltd | Professional & scientific | 2011 |
| Blue Zone Brand Consultancy Limited | Wholesale & retail | 2022 |
| Bluebay Systems Limited | Arts & recreation | 2010 |
| Bluebell Investment Group Ltd | Households | 2023 |
| Bluebell Land Developments Ltd | Construction | 2018 |
| Bluebell Spinney Ltd | Wholesale & retail | 2025 |
| Blueberry Living SL Ltd | Health & social care | 2022 |
| Blueberry Nursery Early Learning Organisation Limited | Education | 2001 |
| Bluebird CRM Limited | Information & communication | 2015 |
| Bluebird Rising Limited | Information & communication | 2025 |
| Bluebird Transport Limited | Transport & logistics | 2003 |
| Bluebird Wholefoods Limited | Wholesale & retail | 2015 |
| Bluebridges Sugar Confectionery Ltd | Manufacturing | 2022 |
| Bluechamp Ltd | Transport & logistics | 2018 |
| Bluechip Cleaning & Maintenance Ltd | Administrative & support | 2020 |
| Bluecoast Limited | Other services | 2018 |
| Bluecoat Academy Trading Limited | Hospitality | 2013 |
| Bluecoat Consultants Limited | Professional & scientific | 2013 |
| Bluecoat Property Limited | Real estate | 2019 |
| Bluedrive Propulsion Ltd | Professional & scientific | 2023 |
| Blueflame GAS & Plumbing Ltd | Construction | 2025 |
| Bluegreen Estates Limited | Administrative & support | 2016 |
| Bluehouse Regeneration Limited | Administrative & support | 2016 |
| Bluejay Financial Planning Ltd | Financial services | 2014 |
| Bluekey Surveys Ltd | Professional & scientific | 2024 |
| Bluelight Electrical Solutions Ltd | Manufacturing | 2020 |
| Blueline Plumbing & Heating Ltd | Construction | 2020 |
| Bluepig Investments Ltd | Real estate | 2016 |
| Bluepool Consult Limited | Professional & scientific | 2024 |
| Blueprint (General Partner) Limited | Real estate | 2005 |
| Blueprint (Nominees) Limited | Real estate | 2005 |
| Blueprint (Nottingham) Limited | Administrative & support | 2000 |
| Blueprint Couriers Limited | Transport & logistics | 2019 |
| Blueprint Design Management Limited | Administrative & support | 2008 |
| Blueprint Group Holdings LLP | | 2019 |
| Blueprint Limited Partnership | | 2005 |
| Blueprint Premier Limited | Manufacturing | 2008 |
| Bluequin Ltd | Information & communication | 2016 |
| Bluerad NO 1 Limited Liability Partnership | | 2014 |
| Bluerock Property Group Ltd | Real estate | 2025 |
| Bluerock Security Ltd | Financial services | 2025 |
| Bluerose Healthcare Ltd | Health & social care | 2024 |
| Blueshift Consulting Limited | Information & communication | 2025 |
| Blueshift Interactive Ltd | Information & communication | 2023 |
| Blueskeye AI Ltd | Information & communication | 2019 |
| Bluess Trading Ltd | Wholesale & retail | 2022 |
| Bluestaff Limited | Construction | 2025 |
| Bluestone Cosmetics Ltd | Wholesale & retail | 2024 |
| Bluethorn Trading Limited | Other services | 2019 |
| Bluetree Healthcare Limited | Administrative & support | 2014 |
| Bluewhalespa Ltd | Wholesale & retail | 2011 |
| Bluewolf Computers Limited | Other services | 2023 |
| Blugilt Holdings Limited | Professional & scientific | 1936 |
| Blugilt Information Technologies Limited | Information & communication | 2023 |
| Blugilt Peterlee Limited | Water & waste | 1978 |
| Blusource Accountancy (EM) Ltd | Administrative & support | 2023 |
| Blusource Accountancy Practice (Regions) LLP | | 2011 |
| Blusource Finance Limited | Administrative & support | 2009 |
| Blusource Professional Services Limited | Administrative & support | 2008 |
| Blustream Ltd | Wholesale & retail | 2015 |
| Blutech Software Limited | Hospitality | 2000 |
| Blutek Enterprise Ltd | Financial services | 2025 |
| Blutek Group Ltd | Construction | 2022 |
| Blutek Holdings Ltd | Financial services | 2025 |
| Blutek Installations Ltd | Construction | 2024 |
| Blutek Sign Maintenance Ltd | Manufacturing | 2026 |
| Blutek Signs Ltd | Construction | 2018 |