| Bradleyrailconsulting Limited | Construction | 2026 |
| Bramley Court (Loughgall) Management Ltd | Extraterritorial | 2005 |
| Brandenburg (Services for Property Developers) Ltd | Administrative & support | 2000 |
| Bratwell Hill Farm Limited | Agriculture & fishing | 2025 |
| Breagh Hill Management Company Limited | Households | 2003 |
| Breckenhill Limited | Wholesale & retail | 2004 |
| Bric Contracts Limited | Construction | 2017 |
| Broadisland Heights Management Company Limited | Households | 2024 |
| Bronze BT 11 Ltd | Other services | 2026 |
| Bronze BT4 Limited | Other services | 2025 |
| Bronze BT43 Ltd | Other services | 2026 |
| Brook 1979 Limited | Extraterritorial | 2013 |
| Brookdale Manor Management Limited | Households | 2007 |
| Browns Removal & Storage Ltd | Transport & logistics | 2008 |
| BRS Genealogy Limited | Information & communication | 2011 |
| Bruslee Maintenance Contracts Ltd | Administrative & support | 2019 |
| Bryantang Meadows Management Ltd | Households | 2009 |
| Buchanan Ceilings & Partitions Ltd | Construction | 2023 |
| Buchanan's (Northern Ireland) Limited | Manufacturing | 2000 |
| Buildtrade Systems Ltd | Extraterritorial | 2022 |
| Bumbles Delicatessen Ltd | Manufacturing | 2017 |
| Burdett Consulting Ltd | Information & communication | 2020 |
| Burnbrae Management Limited | Households | 2002 |
| Bush Road Land and Property Management Ltd | Households | 2016 |
| Bush Road Management Company Limited | Extraterritorial | 2007 |
| Buttermilk Loney Management Ltd | Households | 2017 |
| Caffè Cartel Ltd | Manufacturing | 2025 |
| Calm With Carole Ltd | Health & social care | 2019 |
| Camco Construction Ltd. | Construction | 2016 |
| Cameron Crowe Limited | Transport & logistics | 2003 |
| Camlin Trading Limited | Hospitality | 2017 |
| Campbell Draughting Solutions Ltd | Administrative & support | 2011 |
| Candle DE LA Creme Limited | Manufacturing | 2017 |
| Candlemill Consulting Ltd | Professional & scientific | 2025 |
| Canine Lodgings Ltd | Other services | 2023 |
| Captivology Ltd | Professional & scientific | 2024 |
| Car Commercial Limited | Wholesale & retail | 2013 |
| Caragh Isla Photography Ltd | Professional & scientific | 2025 |
| Carbonwise Group Ltd | Professional & scientific | 2025 |
| Carclub(Ni) Ltd | Wholesale & retail | 2017 |
| Caren Trikelion Limited | Professional & scientific | 2018 |
| Cargill Properties Ltd | Real estate | 2022 |
| Carmichael's Bar | Hospitality | 2015 |
| Carn Engineering Limited | Professional & scientific | 2022 |
| Carn Holdings Limited | Households | 2025 |
| Carnbank Property Management Ltd | Extraterritorial | 2005 |
| Carnlea Consultancy Limited | Professional & scientific | 2019 |
| Carnmoney Court Management Company Limited | Extraterritorial | 2004 |
| Carnwood Management Limited | Extraterritorial | 2003 |
| Carolyn Stewart Broadcast Media Ltd | Information & communication | 2025 |
| Carrickfergus Marina Apartments Services Limited | Extraterritorial | 2000 |
| Carrigart Crescent Management Company Limited | Extraterritorial | 2004 |
| Carrigart Manor Management Company Limited | Extraterritorial | 2004 |
| Cassies Lane Management Company Limited | Households | 2018 |
| Castle Brae Management Company Limited | Households | 2019 |
| Castlegate (Ballyclare) Land Management Ltd | Households | 2026 |
| Castlegate (Ballymena) Property Management Limited | Households | 2020 |
| Castlelodge Gardens Land Management Ltd | Households | 2022 |
| Causeascene Films Limited | Information & communication | 2014 |
| Cavehill Distributors Limited | Wholesale & retail | 2019 |
| CDL Film Limited | Manufacturing | 2025 |
| Cedar Lodge Property Management Ltd | Extraterritorial | 2004 |
| Celeritatem Limited | Financial services | 2024 |
| Celsio Limited | Information & communication | 2017 |
| Central Core Limited | Construction | 2026 |
| Chapel Road Cookstown Management Ltd | Extraterritorial | 2016 |
| Chapter House Properties Ltd | Hospitality | 2012 |
| Cheap Deals Away Ltd | Wholesale & retail | 2004 |
| Cherrington Management Co Ltd | Extraterritorial | 2004 |
| Chichester Park Land Management Ltd | Households | 2022 |
| Chris Campbell Engineering Solutions Limited | Manufacturing | 2016 |
| Christopher Taggart Ltd | Wholesale & retail | 2025 |
| Church Meadows Property Management Co Ltd | Households | 2022 |
| Church Road Property Management Ltd | Extraterritorial | 2007 |
| Church View Manor Management Company Limited | Real estate | 2010 |
| Cicero Ltd | Hospitality | 2023 |
| City Blinds Limited | Manufacturing | 1986 |
| CJD Agri Limited | Construction | 2016 |
| Clady Water Enterprises Ltd | Construction | 2010 |
| Claire Lunn Wealth Management Ltd | Professional & scientific | 2025 |
| Clanbrassil Management Ltd | Extraterritorial | 1998 |
| Clare Creative Ltd | Professional & scientific | 2008 |
| Clare Grounds Maintenance Ltd | Real estate | 2013 |
| Clareview Agri Ltd | Wholesale & retail | 2013 |
| Clearview Solutions (N.I.) Ltd | Construction | 2025 |
| Clements Hall Land Management Co Ltd | Households | 2017 |
| Cloghogue Service Station Ltd | Wholesale & retail | 2020 |
| Clonvara Management Company Limited | Real estate | 2003 |
| Clothing Collections International Ltd | Wholesale & retail | 2003 |
| Cloud N9NE Ballyclare Ltd | Wholesale & retail | 2025 |
| Cloughfin View Management Ltd | Extraterritorial | 2013 |
| Cloughogue Service Station Limited | Wholesale & retail | 2018 |
| Clover Brook Management Ltd | Households | 2016 |
| Cluaneo Meadows Land Management Ltd | Extraterritorial | 2004 |
| Clyde Agri Contracts Limited | Agriculture & fishing | 2015 |
| CM Waste Services Limited | Water & waste | 2020 |
| CMW (NI) Limited | Hospitality | 2013 |
| Co. Antrim Indoor Bowling Club Ltd | Other services | 2014 |
| Coast Catering Limited | Hospitality | 2019 |
| Cogry Services Ltd | Administrative & support | 2023 |