| Binevenagh Adventures Ltd | Education | 2020 |
| Binevenagh Properties Limited | Construction | 2009 |
| Binh LE Ltd | Wholesale & retail | 2025 |
| Biopac (UK) Limited | Wholesale & retail | 2016 |
| Biovald Ltd | Professional & scientific | 2025 |
| Birch Water Properties Limited | Real estate | 2026 |
| Bitberg Trading Ltd | Manufacturing | 2023 |
| Bits 'N' Pieces (Derry) Limited | Wholesale & retail | 2006 |
| BJ Four Season Ltd | Hospitality | 2024 |
| BK Legal Services Ltd | Professional & scientific | 2021 |
| BKR Farming Limited | Agriculture & fishing | 2021 |
| BL Investments Limited | Wholesale & retail | 2020 |
| Black & Adams Homes Limited | Construction | 1992 |
| Black North Group Limited | Information & communication | 2025 |
| Blackbrae Parke Engineering (NI) Limited | Other services | 2019 |
| Blackeyes Trading Limited | Real estate | 2012 |
| Blackgrass Design Engineering Limited | Extraterritorial | 2012 |
| Blackland Properties Ltd | Real estate | 2002 |
| Blazequel Ltd | Wholesale & retail | 2013 |
| Blockception Ltd | Arts & recreation | 2017 |
| Blue Badge Tours Ltd | Administrative & support | 2022 |
| Blue Coat School Heritage Centre | Arts & recreation | 2018 |
| Blue Inspiration Ltd | Information & communication | 2014 |
| BMC Construction Limited | Construction | 1999 |
| BMG Electrical Services Ltd | Manufacturing | 2024 |
| BMSG786 Ltd | Wholesale & retail | 2024 |
| BMULLAN91 Limited | Information & communication | 2015 |
| Bogside and Brandywell Health Forum | Other services | 2007 |
| Boiler Systems NI Ltd | Construction | 2017 |
| Bond Street Stores Ltd | Wholesale & retail | 2018 |
| Bonner International Transport and Civil Limited | Transport & logistics | 2015 |
| Book Entertainment Limited | Administrative & support | 2016 |
| Boomhall Trust | Education | 2019 |
| Bops Retail Ltd | Wholesale & retail | 2024 |
| Borderlink Recruitment Ltd | Administrative & support | 2023 |
| Botanic Leisure Limited | Arts & recreation | 2009 |
| Bounce Away Entertainment Ltd | Arts & recreation | 2013 |
| Boutique Breaks Limited | Arts & recreation | 2025 |
| BOWIE1954 Ltd | Manufacturing | 2021 |
| Boxmore Properties Ltd | Real estate | 2025 |
| Boyan Drylining Ltd | Construction | 2014 |
| Boyce Paint & Tiles Ltd | Wholesale & retail | 2012 |
| Boyle Services Limited | Administrative & support | 2019 |
| Bracka Investments Limited | Real estate | 1999 |
| Bracken Stores Limited | Wholesale & retail | 2022 |
| Brackfield Old School Ltd | Other services | 2000 |
| Brae Properties Ltd | Real estate | 2018 |
| Braidwater (Ballyclare) Limited | Construction | 2025 |
| Braidwater Group Limited | Construction | 2018 |
| Braidwater Holdings Limited | Construction | 2008 |
| Braidwater Land Limited | Construction | 2021 |
| Braidwater Limited | Construction | 2011 |
| Braidwater Residences Limited | Real estate | 2019 |
| Brand Guide Ltd | Professional & scientific | 2023 |
| Brandbnk Ltd | Information & communication | 2026 |
| Brandcanvas Ltd | Information & communication | 2023 |
| Brandywell Greyhound Racing Company (1976) Limited | Arts & recreation | 1976 |
| Brandywell Stores Ltd | Wholesale & retail | 2023 |
| Bratulescu Ltd | Health & social care | 2015 |
| Brendara Limited | Financial services | 2021 |
| Breslin's Family Butchers Ltd | Wholesale & retail | 2010 |
| Brew Bros Coffee Ltd | Hospitality | 2025 |
| Brian Foster Productions Limited | Arts & recreation | 2022 |
| Brian Mcmanus Car Sales Limited | Wholesale & retail | 2017 |
| Brickwork Two Limited | Hospitality | 2017 |
| Bridge Accommodations Limited | Hospitality | 2019 |
| Bridgehill Real Estate Ltd | Real estate | 2019 |
| Brimac Security Limited | Administrative & support | 2014 |
| Brisket Ltd | Hospitality | 2016 |
| Britannia Hall Ltd. | Real estate | 2013 |
| BRM Group Ltd | Financial services | 2020 |
| BRM Plant Hire & Sales Ltd | Construction | 2018 |
| BRM Real Estate Ltd | Real estate | 2021 |
| BRM Utility Services Ltd | Construction | 2016 |
| Broadband N.I. Ltd | Information & communication | 2006 |
| Broadway Tavern Limited | Hospitality | 1990 |
| Brockagh Heights Renewables Limited | Energy | 2026 |
| Broconus Ltd | Information & communication | 2025 |
| Brolly Coyle Limited | Wholesale & retail | 2016 |
| Bronte and Co. Limited | Real estate | 2014 |
| Brook Hall Outreach CIC | Professional & scientific | 2024 |
| Brookmount Management Company (Altnagelvin) Limited | Households | 2017 |
| Broomhill Mews Management Limited | Real estate | 1996 |
| Broomhill Ventures Ltd | Real estate | 2015 |
| Brownandco Ltd | Hospitality | 2019 |
| Brownsandcompany Ltd | Hospitality | 2024 |
| Bruno Shop Ltd | Wholesale & retail | 2021 |
| Bryan Smyth Engineering Limited | Professional & scientific | 2025 |
| BSM Investments Limited | Real estate | 2013 |
| BT4 Safety Sollutions Ltd. | Professional & scientific | 2011 |
| BT47 Digital Ltd | Construction | 2024 |
| BTM Health Care Ltd | Health & social care | 2026 |
| Bubblebum Holdings Limited | Financial services | 2012 |
| Buldinsun Ltd | Wholesale & retail | 2026 |
| Burbun Developments Limited | Real estate | 2023 |
| Burlington Projects Ltd | Real estate | 2016 |
| Burnfoot Community Development Association | Education | 2012 |
| Burns Pharm Ltd | Wholesale & retail | 2023 |
| Bury Street Projects Ltd | Real estate | 2022 |
| Business Iapps Limited | Professional & scientific | 2014 |