| Banbridge Nails Ltd | Other services | 2026 |
| Banbridge Specsavers Limited | Wholesale & retail | 2016 |
| Banbridge Website Studio Limited | Information & communication | 2020 |
| Bangor Rentals NI Ltd | Real estate | 2016 |
| Bann 12 Limited | Real estate | 2012 |
| Bann Architectural Systems Limited | Manufacturing | 2010 |
| Bann Commercial NI Limited | Real estate | 2022 |
| Bann Haulage Co.Limited | Transport & logistics | 1983 |
| Bann Hire (Lisburn) LLP | | 2013 |
| Bann Hospitality Ltd | Hospitality | 2025 |
| Bann Joinery & Flooring Ltd | Construction | 2015 |
| Bann Machinery LLP | | 2015 |
| Bann Properties Limited | Real estate | 2022 |
| Bann Stationers and Photo Print Specialists Limited | Administrative & support | 2024 |
| Bannfield Construction Ltd | Construction | 2023 |
| Bannfitzone Limited | Arts & recreation | 2016 |
| Banties Ltd | Extraterritorial | 2012 |
| BASE22 Financial Ltd | Real estate | 2025 |
| BD Testing Solutions Limited | Information & communication | 2019 |
| Beechrow Limited | Real estate | 1998 |
| Belfast City Cleaning Services Limited | Administrative & support | 2025 |
| Belfast True Pilates Studio Limited | Arts & recreation | 2025 |
| Bellevue Cottage (Killowen) Ltd | Real estate | 2023 |
| Bemack Limited | Wholesale & retail | 2012 |
| Bespoke Transformations Limited | Construction | 2019 |
| Big Head Solutions Ltd | Professional & scientific | 2018 |
| BIN 66 Ltd | Hospitality | 2014 |
| Biogas Energy Limited | Energy | 2015 |
| BJK Building Construction Ltd | Construction | 2020 |
| Black COW Agencies Ltd | Financial services | 2025 |
| Black COW Consultancy Limited | Professional & scientific | 2025 |
| Black COW Holdings Limited | Financial services | 2026 |
| Blackskull Investments Limited | Financial services | 2026 |
| BLAKELY247 Ltd | Wholesale & retail | 2013 |
| Bloomin' Doll Ltd | Wholesale & retail | 2019 |
| Blue Coatings Ltd | Manufacturing | 2024 |
| Bluepoint Networks Limited | Information & communication | 2014 |
| BMT Investments Limited | Real estate | 2016 |
| Bobs Plumbers Ltd. | Construction | 2022 |
| Botanic Avenue Properties Limited | Real estate | 2018 |
| Bounce FM Ltd | Information & communication | 2017 |
| Boutique Stays-Ni Ltd | Hospitality | 2023 |
| Bowman Windows Limited | Construction | 2012 |
| BP Jewellery Europe Ltd | Wholesale & retail | 2025 |
| Brainstate Ltd | Health & social care | 2021 |
| Brand Elevation Solutions Ltd | Professional & scientific | 2017 |
| Branniff Joinery & Fit OUT Ltd | Manufacturing | 2023 |
| Branniff Joinery Ltd | Construction | 2011 |
| Bridge 12 Ltd | Real estate | 2012 |
| Bridge Counselling & Supervision Ltd | Health & social care | 2019 |
| Bridge Energy (NI) Limited | Energy | 2014 |
| Bridge Energy Farms Limited | Real estate | 2015 |
| Bridge Energy Services (NI) Limited | Agriculture & fishing | 2014 |
| Bridge Ford Properties Limited | Hospitality | 2017 |
| Bridge Primary Limited | Extraterritorial | 1987 |
| Bridgedown Property Ltd | Real estate | 2026 |
| Bridgesthair Limited | Other services | 2024 |
| Brimatt Enterprises Limited | Wholesale & retail | 2013 |
| Brni Ltd | Real estate | 2019 |
| Bronte Stables Limited | Agriculture & fishing | 2013 |
| Bruce Casey Holdings Ltd | Professional & scientific | 2026 |
| BSM Electrical Limited | Construction | 2011 |
| BSS Total Solutions Ltd | Other services | 2026 |
| BT32 Collective Ltd | Other services | 2026 |
| Buildcon Homes Limited | Construction | 2003 |
| Building Access Support & Engagement Limited | Health & social care | 2026 |
| Building Envelope Technologies Limited | Energy | 2016 |
| Burns Skills School Limited | Arts & recreation | 2018 |
| Business of AI Club Limited | Information & communication | 2025 |
| C25 Ltd | Manufacturing | 2025 |
| Cafe Marmalade Limited | Hospitality | 2016 |
| Callum Mccandless Ltd | Health & social care | 2023 |
| Camlo Investments Ltd | Hospitality | 2022 |
| Camlo Properties Ltd | Construction | 2016 |
| Campsbay Limited | Professional & scientific | 2021 |
| Cannabaseni Ltd | Wholesale & retail | 2024 |
| Caplu Limited | Administrative & support | 2013 |
| Cappard Limited | Real estate | 2015 |
| Captain Container Limited | Transport & logistics | 2013 |
| Card Cave Ltd | Wholesale & retail | 2015 |
| Carindale Investments Limited | Real estate | 2020 |
| Carlton Belleek Ltd | Real estate | 2015 |
| Carrick Road Energy IRL Ltd | Energy | 2017 |
| Carrick Road Enterprises Limited | Agriculture & fishing | 2025 |
| Carrick Road Holdings Limited | Energy | 2016 |
| Carrillo Care(Ni) Ltd | Health & social care | 2025 |
| Cartloom Ltd | Wholesale & retail | 2026 |
| Carvill (Ballyoran) Limited | Construction | 2018 |
| Carvill Construction (Star Mill) Ltd | Construction | 2024 |
| Carvill Developments (Star Mill) Ltd | Construction | 2021 |
| Carvill Developments Ltd. | Construction | 2011 |
| CAS Group N. Ireland Ltd | Construction | 2019 |
| Casa Felici NI Limited | Wholesale & retail | 2017 |
| Cash House Buyer (N.I.) Ltd | Real estate | 2022 |
| Cashelmara Cass Limited | Professional & scientific | 2010 |
| Castle Capital Limited | Financial services | 2022 |
| CCH Homes NI Ltd | Hospitality | 2021 |
| Cenprom Limited | Real estate | 2020 |
| Central Promenade Management (Newcastle) Limited | Households | 2017 |
| Chain Care Lifting Services Limited | Administrative & support | 2006 |