| Battery Harbour Company Ltd -the | Arts & recreation | 2001 |
| Bawn Office Services Ltd | Other services | 2014 |
| Bay Crescent Company Limited | Financial services | 2021 |
| Bay of Bengal (Cookstown) Ltd | Hospitality | 2021 |
| BD Ecom Ltd | Wholesale & retail | 2025 |
| BD Ireland Limited | Wholesale & retail | 2024 |
| Beauty With Chloe Ltd | Other services | 2019 |
| Beckett Roofing Services Limited | Manufacturing | 2009 |
| Bedford Street Investments Limited | Financial services | 2015 |
| BEE Happy Shop Ltd | Wholesale & retail | 2023 |
| Beeches Avenue Company Limited | Professional & scientific | 2019 |
| Beechill Estates Ltd | Construction | 2024 |
| Begerin Enterprises Limited | Wholesale & retail | 2018 |
| Bell Contracts & Co Ltd | Construction | 2010 |
| Bell Paints Ltd | Wholesale & retail | 2014 |
| BHI Stores (2) Ltd | Wholesale & retail | 2026 |
| BHI Stores Ltd | Energy | 2016 |
| Bickers Dornan Wholesale Limited | Wholesale & retail | 2015 |
| Big POT Co. Ltd | Manufacturing | 2009 |
| Bigbridge Farm Ltd | Agriculture & fishing | 2026 |
| Bike Competitions NI Ltd | Arts & recreation | 2025 |
| Bill Eastwood Contracts Ltd | Construction | 2023 |
| Biogas (N.I.) Ltd | Energy | 2019 |
| Birch Avenue Company Limited | Extraterritorial | 2015 |
| Birch Terrace Company Limited | Construction | 2015 |
| Birch Tree Company NO 1 Limited | Real estate | 2014 |
| Birch Tree Company NO 3 Limited | Professional & scientific | 2014 |
| BJQ Contracts Ltd | Construction | 2014 |
| Black Contracts Ltd | Agriculture & fishing | 2004 |
| BLU DOT Technologies Limited | Information & communication | 2017 |
| Bludot Mobility Limited | Information & communication | 2025 |
| Bodrum Property Direct Limited | Extraterritorial | 2006 |
| Bomacs Limited | Real estate | 2022 |
| Booth Plumbing Limited | Construction | 2011 |
| Bored of Lunch Ltd | Other services | 2021 |
| Bosti Ltd | Wholesale & retail | 2022 |
| BR Engineering (N.I) Ltd | Manufacturing | 2019 |
| Braeside Farm Eggs Ltd | Wholesale & retail | 2023 |
| Bramble Farm Ltd | Agriculture & fishing | 2011 |
| Branch OUT Carpentry Ltd | Construction | 2023 |
| Brea Limited | Real estate | 2014 |
| Brent (N0. 190) Limited | Financial services | 2021 |
| Bridgefield Agri Ltd | Other services | 2024 |
| Brigh Wind Ltd | Energy | 2012 |
| Brirish Limited | Manufacturing | 2015 |
| Brisbane Electrical Services Ltd | Construction | 2015 |
| Bronte Property Limited | Real estate | 2025 |
| Brookeborough Developments Limited | Construction | 2022 |
| Brookmount Holdings Ltd | Wholesale & retail | 2009 |
| Brown Boys T/A Apache Pizza Ltd | Hospitality | 2021 |
| Brown EGG Media Limited | Information & communication | 2007 |
| Brownstone Estates Ltd | Construction | 2018 |
| Bruce Engineering Services (NI) Limited | Manufacturing | 2009 |
| BT80 - the Collective Ltd | Other services | 2024 |
| BTE Contracts Ltd | Construction | 2024 |
| Building Products Distributors Limited | Wholesale & retail | 1992 |
| Bulldog Inventions (NI) Limited | Professional & scientific | 2021 |
| Burnbank Farms Ltd | Agriculture & fishing | 1990 |
| BW Construction Ltd | Construction | 2022 |
| C G Juelz Cookstown Ltd | Wholesale & retail | 2012 |
| C Mccullagh Contracts Limited | Construction | 2015 |
| C Rafferty Construction Ltd | Construction | 2026 |
| C Scott Property Investments Ltd | Real estate | 2025 |
| C&Z Properties Ltd | Real estate | 2025 |
| C. Mcilvar Ltd | Professional & scientific | 2013 |
| C.C.E. Video Limited | Wholesale & retail | 1983 |
| C.K.S.S. Properties Ltd | Real estate | 2014 |
| Caddy Construction Limited | Construction | 2002 |
| Cady Limited | Manufacturing | 2006 |
| Cairde Corra Chriochach | Other services | 2024 |
| Cajar Ltd | Real estate | 2018 |
| Calon Holdings Ltd | Financial services | 2019 |
| Cambodia Youth for Change | Education | 2012 |
| Canary 7 Ltd | Information & communication | 2022 |
| Cantley Investments Limited | Construction | 2013 |
| Care Bear Creche Ltd | Health & social care | 2009 |
| Care Facilities & Management Limited | Health & social care | 2016 |
| Care Facilities Limited | Health & social care | 1988 |
| Care Facilities Support Services Limited | Administrative & support | 2024 |
| Carnehill Joinery Ltd | Manufacturing | 2011 |
| Cars Depot Ireland Ltd | Wholesale & retail | 2013 |
| Carsm LLP | | 2007 |
| Cassidy Funeral Directors Ltd | Other services | 2026 |
| Caulfield Corporate Risks Limited | Financial services | 2013 |
| Causeway and MID Ulster Women's AID | Other services | 1995 |
| Cavandarragh Wind Ltd | Energy | 2016 |
| CDE Global Limited | Manufacturing | 2000 |
| CDE Group Holdings Limited | Financial services | 2020 |
| CDE International Operations Limited | Financial services | 2025 |
| CDE Manufacturing Limited | Manufacturing | 2018 |
| Cdenviro Limited | Manufacturing | 2010 |
| CDM Community Transport | Transport & logistics | 2011 |
| Central Systems Ireland Ltd | Manufacturing | 2012 |
| Centurion Bulk Ltd | Transport & logistics | 2013 |
| Ceon Machinery Control Ltd | Manufacturing | 2015 |
| Charcas Investments Limited | Financial services | 2022 |
| Charis Cancer Care Ltd | Health & social care | 2008 |
| Cherry Blossoms Rental Ltd | Real estate | 2024 |
| Church Heights Development Management Company Limited | Real estate | 2006 |
| Cianad Software Ltd | Information & communication | 2014 |