| Boydcreative Ltd | Information & communication | 2011 |
| Boyland Group Ltd | Wholesale & retail | 2020 |
| Boyle Co. Limited | Information & communication | 2019 |
| Bracie Ltd | Information & communication | 2025 |
| Brackenwood (Coleraine) Limited | Households | 2010 |
| Bradley & Company Civil Engineering Limited | Construction | 2016 |
| Bradley & Company Communications Limited | Other services | 2016 |
| Bradley & Company Construction Solutions Limited | Construction | 2016 |
| Bradley Fuels Ltd | Wholesale & retail | 2011 |
| Bradley Service Station Ltd | Wholesale & retail | 2011 |
| Bradley Utilities Limited | Other services | 2014 |
| Bradley's Haulage and Plant Hire Ltd | Transport & logistics | 2025 |
| Braid Cladding Limited | Construction | 2018 |
| Braidlough Developments Ltd | Real estate | 2003 |
| Breenobelle Holdings Ltd | Real estate | 2024 |
| Brian Canavan Associates LLP | | 2026 |
| Brian Magee Carousel Limited | Arts & recreation | 2018 |
| Brian Mullan Construction Ltd | Construction | 2006 |
| Brick & Beam Collective Ltd | Real estate | 2024 |
| Bright Growth Holdings Limited | Construction | 2021 |
| Brockaghboy Developments Ltd | Construction | 2021 |
| Brockaghbuoy Civil Engineering Ltd | Construction | 2020 |
| Brockaghbuoy Holdings Ltd | Financial services | 2025 |
| Brocklamont Management Company Ltd | Households | 2023 |
| Brone Park Properties Ltd | Extraterritorial | 2007 |
| Brooklands Dale Management Ltd | Households | 2013 |
| Broomhill Associates Limited | Real estate | 2002 |
| Btfive Limited | Administrative & support | 2026 |
| Burnside Garage Limited | Wholesale & retail | 2006 |
| Bushmills Hydro-Electric Company Limited | Energy | 2007 |
| Bushtown Lifting Ltd | Construction | 2025 |
| C & M Poling Limited | Construction | 2019 |
| C B Services (Contracts) Ltd | Construction | 2011 |
| Cafe 19 Ltd | Hospitality | 2024 |
| Cafe at the Castle Ltd | Hospitality | 2022 |
| Cafe Mews Management Company Limited | Households | 2007 |
| Caherty Hill Property Management Ltd | Households | 2016 |
| Camburn Developments Ltd | Energy | 2021 |
| Campbell Ritchie Chartered Accountants Ltd | Professional & scientific | 2015 |
| Camphill Mews Management Ltd | Extraterritorial | 2007 |
| Campsie Close Management Company Ltd | Households | 2019 |
| Cannongate Capital Limited | Real estate | 2020 |
| Capital Trust Financial Management Ltd | Financial services | 1994 |
| Capital W Properties Ltd | Real estate | 2004 |
| Cappagh Limited | Extraterritorial | 2012 |
| Car & Audio Tune Limited | Wholesale & retail | 1998 |
| Carbut Limited | Construction | 2019 |
| Carhill Cars Limited | Wholesale & retail | 2010 |
| Carnalea Manor Management Limited | Households | 2010 |
| Carnalea Meadows Management Ltd | Households | 2018 |
| Carnroe Supplies Limited | Wholesale & retail | 2007 |
| Carnview Plumbing & Heating Ltd | Construction | 2021 |
| Carrig-Na-Rone Management Company Limited | Households | 2005 |
| Cassidy Bros. (Plumbing & Heating) Limited | Construction | 2008 |
| Cassidy Plumbing & Heating Ltd | Construction | 2025 |
| Castaway Events Ltd | Hospitality | 2025 |
| Castle Barron Ltd | Construction | 2018 |
| Castle Engineering & Crane Hire Ltd | Administrative & support | 2007 |
| Castle Manor Management Company Limited | Real estate | 2009 |
| Castle Square Capital Ltd | Real estate | 2017 |
| Castle Upton Management Company Limited | Households | 1990 |
| Castlecatt Landscape Management Limited | Households | 2004 |
| Castlemore Trading Limited | Hospitality | 2020 |
| Castlerock Community Association | Other services | 2011 |
| Castlerock Holiday Parks Holdings Ltd | Financial services | 2025 |
| Castlerock Holiday Parks Ltd | Hospitality | 2025 |
| Castlerock Property Management Limited | Real estate | 2010 |
| Cathan Construction Limited | Construction | 2015 |
| Cathan Property Management Limited | Real estate | 2024 |
| Causeway 1ST AID & Training Ltd | Arts & recreation | 2013 |
| Causeway Adventures Limited | Arts & recreation | 2016 |
| Causeway Apartments Management Company Ltd | Real estate | 2015 |
| Causeway Association of Urban Sports | Arts & recreation | 2024 |
| Causeway Business Connect Limited | Wholesale & retail | 2023 |
| Causeway Campers Limited | Administrative & support | 2013 |
| Causeway Capital Limited | Real estate | 2014 |
| Causeway Career Coaching Ltd | Administrative & support | 2019 |
| Causeway Chamber of Commerce | Other services | 1920 |
| Causeway Cleaning Ltd | Other services | 2012 |
| Causeway Coast Aesthetics Ltd | Other services | 2017 |
| Causeway Coast Combat Academy CIC | Arts & recreation | 2021 |
| Causeway Coast Dog Rescue Limited | Agriculture & fishing | 2010 |
| Causeway Coast Escapes Ltd | Real estate | 2026 |
| Causeway Coast Projects Limited | Extraterritorial | 2016 |
| Causeway Coast Vineyard Church | Other services | 2008 |
| Causeway Commercial Exports Ltd | Wholesale & retail | 2021 |
| Causeway Connections Limited | Other services | 2020 |
| Causeway Court Residents Limited | Households | 1989 |
| Causeway Craft & Coffee Ltd | Hospitality | 2024 |
| Causeway Digital Ltd | Information & communication | 2020 |
| Causeway Eats Ltd | Hospitality | 2022 |
| Causeway Empowerment Programme Ltd | Health & social care | 2024 |
| Causeway Fitness Limited | Arts & recreation | 2020 |
| Causeway Inspection Services Ltd | Professional & scientific | 2023 |
| Causeway IT Services Limited | Administrative & support | 2022 |
| Causeway Leak Detection Ltd | Construction | 2019 |
| Causeway Organic CIC | Wholesale & retail | 2025 |
| Causeway Pest Control Ltd | Administrative & support | 2025 |
| Causeway Rural & Urban Network | Administrative & support | 2005 |
| Causeway School of Music Ltd | Education | 2019 |