| Business Education Partnership (UK) Ltd | Other services | 1992 |
| Business Exchange Essex Ltd | Financial services | 2018 |
| Business Help UK Limited | Professional & scientific | 2005 |
| Business One Limited | Wholesale & retail | 2015 |
| Business Rate Saver Limited | Administrative & support | 2013 |
| Business Sorted Services Ltd | Professional & scientific | 2023 |
| Business Taxation Accountants Ltd | Professional & scientific | 2009 |
| Bustle Group Limited | Wholesale & retail | 2023 |
| Busu Trans Ltd | Transport & logistics | 2016 |
| Busy BEE Services Ltd | Administrative & support | 2021 |
| Busybodies Wellness Ltd | Other services | 2022 |
| Butas Transport Ltd | Transport & logistics | 2025 |
| Butique Fashionable Ltd | Wholesale & retail | 2025 |
| Butler Bricklayers & Builders Ltd | Construction | 2011 |
| Butnaru Electrical Ltd | Construction | 2019 |
| Butt Properties Limited | Real estate | 2017 |
| Butterbeans Daycare Ltd | Health & social care | 2022 |
| Butterfly Social Housing Ltd | Households | 2024 |
| Butterfly Training Ltd | Administrative & support | 2024 |
| Buttrevive Ltd | Water & waste | 2025 |
| Buttrfly Haus Ltd | Information & communication | 2020 |
| Buy Click Ltd | Wholesale & retail | 2020 |
| BUY2BRAND Ltd | Wholesale & retail | 2026 |
| Buzzbytes Design & Marketing Ltd | Professional & scientific | 2024 |
| Buzzconnekt Business Solutions Ltd | Administrative & support | 2024 |
| Buzzpoint Limited | Information & communication | 2012 |
| BVA Construction Ltd | Construction | 2021 |
| BVE Property Consultants Ltd | Professional & scientific | 2004 |
| BVL Construct Ltd | Construction | 2021 |
| BW Residences Ltd | Real estate | 2025 |
| Bw&S Ltd | Wholesale & retail | 2020 |
| BWH Developments Limited | Construction | 2019 |
| Bwilliams Consulting Services Ltd | Professional & scientific | 2015 |
| Bwjdalmc Limited | Wholesale & retail | 2021 |
| BWM Logistics Ltd | Professional & scientific | 2025 |
| BX1 Group Ltd | Administrative & support | 2021 |
| Bxnmxclean Ltd | Professional & scientific | 2025 |
| BY Cristina's Limited | Hospitality | 2026 |
| BY Robin Limited | Manufacturing | 2008 |
| BYE INT Ltd | Administrative & support | 2025 |
| Byfaryal Ltd | Wholesale & retail | 2025 |
| BYK Homes Limited | Real estate | 2023 |
| Byt&Kev Ltd | Construction | 2023 |
| Bytepulse Limited | Wholesale & retail | 2023 |
| BZR & Co Limited | Hospitality | 2019 |
| Bztv Limited | Information & communication | 2022 |
| Bélu Ltd | Wholesale & retail | 2025 |
| C & C Grand Homes Limited | Households | 2020 |
| C & G Bookmakers Ltd | Arts & recreation | 2024 |
| C & S Textiles and Recycling Limited | Wholesale & retail | 2013 |
| C & Z Construction Services Ltd | Construction | 2021 |
| C and a Active Services Ltd | Construction | 2022 |
| C E B Limited | Administrative & support | 2018 |
| C F Locum Ltd | Health & social care | 2023 |
| C J Ankomah Company Ltd | Construction | 2025 |
| C James London Ltd | Real estate | 2010 |
| C K Films Limited | Administrative & support | 2009 |
| C Moore Limited | Health & social care | 2016 |
| C T R Automotive Limited | Transport & logistics | 2025 |
| C WHIT3 Limited | Wholesale & retail | 2023 |
| C&A and Sons Limited | Construction | 2022 |
| C&A Drywall Ltd | Construction | 2020 |
| C&A Surplus Ltd. | Real estate | 2018 |
| C&A Trading and Services Ltd | Transport & logistics | 2024 |
| C&A Trans Spedition Ltd | Transport & logistics | 2014 |
| C&M Recovery Limited | Wholesale & retail | 2023 |
| C&M Supreme Services Ltd | Transport & logistics | 2019 |
| C&W Hospitality Projects Limited | Construction | 2023 |
| C&W Projects Limited | Construction | 2025 |
| C&W Workplace Projects Limited | Construction | 2024 |
| C'Ameaa Ltd | Construction | 2021 |
| C. Dell Services Ltd | Construction | 2026 |
| C.B.R Ltd | Hospitality | 2018 |
| C.Chasney Limited | Financial services | 1955 |
| C.D.C. (Flooring and Fabrics) Limited | Construction | 1978 |
| C.E.C. Professional Cleaning Limited | Administrative & support | 2020 |
| C.E.P.W. (London) Limited | Wholesale & retail | 2010 |
| C.F.L. Southeast Ltd | Construction | 2019 |
| C.K Properties Limited | Health & social care | 2021 |
| C.T Guards UK Limited | Administrative & support | 2006 |
| C.W. Smith and Sons (Removals) Limited | Transport & logistics | 1973 |
| C2J Bars Ltd | Hospitality | 2019 |
| C2M Builders Limited | Construction | 2024 |
| C4CLEANER Ltd | Administrative & support | 2025 |
| CAA Duca Limited | Construction | 2024 |
| Caanes.Metinco Ltd | Real estate | 2026 |
| CAB Connect Properties Ltd | Real estate | 2026 |
| Cabod Investments Limited | Financial services | 2018 |
| Caci Bros Ltd | Professional & scientific | 2023 |
| CAD Drylining Ltd | Construction | 2017 |
| Cadre Systems Limited | Information & communication | 2025 |
| Cadv Engineering Ltd | Construction | 2016 |
| Cafe 52 Ltd | Hospitality | 2020 |
| Cafe Ella Limited | Hospitality | 2024 |
| Cafe Royale 2 Limited | Hospitality | 2017 |
| Caffe Italiano London Ltd | Hospitality | 2017 |
| Cafla Limited | Hospitality | 2025 |
| Café Shot Ltd. | Hospitality | 2016 |
| Cake by Slice Ltd | Manufacturing | 2025 |
| Cake Inn Chadwell Heath Ltd | Wholesale & retail | 2025 |