| Bopharm Investments Ltd | Financial services | 2022 |
| Bopharm Ltd | Health & social care | 2016 |
| BOS & Co Drylining Limited | Construction | 2004 |
| Box Displays Holdings Limited | Wholesale & retail | 2022 |
| Brae Limited | Real estate | 2018 |
| Bratwell Equine Limited | Agriculture & fishing | 2025 |
| Brian Mccracken Limited | Construction | 1998 |
| Briar Hill Greysteel Management Limited | Households | 2012 |
| Bridge House Court Management Company Limited | Households | 2002 |
| Bridge Landscape Management Limited | Households | 2004 |
| Broadstone Management Company Limited | Households | 2012 |
| Building Solutions (NI) Ltd | Construction | 2014 |
| Burkus Ltd | Information & communication | 2023 |
| C L Electric Limited | Construction | 2012 |
| C O'Kane Plumbing Limited | Construction | 2022 |
| C Wilson Developments Ltd | Construction | 2023 |
| C.O.A.S.T. (Causeway Older Active Strategic Team) | Other services | 2015 |
| C.S.G. (Training) Ltd | Education | 2004 |
| Cafe on the SQUARE.1 Ltd | Hospitality | 2023 |
| Cairbre Limited | Wholesale & retail | 2025 |
| Callaghan Housing Ltd | Real estate | 2021 |
| Calmore Court (NI) Management Company Limited | Households | 2026 |
| Camco Mechanical Services Ltd | Professional & scientific | 2025 |
| Camel Sales Ltd | Professional & scientific | 2020 |
| Camlah Ltd | Health & social care | 2025 |
| Canning's Homes Ltd | Professional & scientific | 2020 |
| Canterbury Park Management Company Limited | Households | 2025 |
| Capital Lease Funding Ltd | Real estate | 2025 |
| Carrickvale Management Company Ltd | Households | 2025 |
| Carrowclare Consulting Limited | Professional & scientific | 2023 |
| Casa Developments N.I Ltd | Real estate | 2025 |
| Cashlandoo Ltd | Hospitality | 2025 |
| Caskie Eyecare Ltd | Wholesale & retail | 2025 |
| Castle Croft Drive Management Company Limited | Households | 2019 |
| Castle Erin Management Company Ltd | Households | 2023 |
| Castlegreen Farms Limited | Agriculture & fishing | 2011 |
| Castlehill Property Management Company Limited | Households | 2018 |
| Castleroe Management Company Limited | Households | 2008 |
| Causeway Caravans Ltd | Hospitality | 2025 |
| Causeway Funding Solutions Ltd | Professional & scientific | 2026 |
| Causeway Packaging Limited | Wholesale & retail | 2024 |
| CB Motors Eglinton Ltd | Wholesale & retail | 2020 |
| CBC Building Services Limited | Construction | 2014 |
| CBD Roevalley Ltd | Wholesale & retail | 2019 |
| Cdes (FR) Ltd | Wholesale & retail | 2026 |
| Central Electrical Services N.I. Limited | Wholesale & retail | 2023 |
| Ceres Group Europe (NI) Ltd | Education | 2012 |
| Chairman Investments Limited | Financial services | 2019 |
| Charles Close Management Company Limited | Households | 2006 |
| Cherrybrook Property Management Ltd | Households | 2021 |
| Cherrydene Apartments Management Limited | Households | 2020 |
| Cherrydene Residential Management Limited | Households | 2020 |
| Chipsni Ltd | Hospitality | 2024 |
| Chopstick Limavady Ltd | Hospitality | 2025 |
| Chris Donaghy Design Ltd | Manufacturing | 2018 |
| Church Mews Cookstown Management Company Ltd | Households | 2023 |
| CJA Asset Management Limited | Professional & scientific | 2021 |
| CL Offshore Ltd | Mining & quarrying | 2022 |
| Clondara Consulting Ltd | Professional & scientific | 2020 |
| Cloneen Manor Ltd | Households | 2003 |
| Clonlee Properties Ltd | Real estate | 2021 |
| Clooney Distillery Limited | Manufacturing | 2024 |
| Clooney Trading Limited | Financial services | 2023 |
| Cloughan Management Company Ltd | Households | 2023 |
| Cloughan View Management Company Ltd | Households | 2025 |
| CMC Company (NI) Ltd | Construction | 2014 |
| Cmccic Ltd | Real estate | 2025 |
| Coastal Core Ltd | Education | 2017 |
| Coastal Links Management Company Ltd | Households | 2018 |
| Cobalt LED Limited | Wholesale & retail | 2025 |
| Coffee Solutions (Ireland) Ltd | Manufacturing | 2014 |
| Coleraine and District Society of Model Engineers Ltd | Arts & recreation | 1991 |
| Coll Developments NI Ltd | Construction | 2017 |
| College Development (Greystone Road) Management Company Limited | Households | 2005 |
| College Green Apartments Management Company Ltd | Households | 2023 |
| College Place Management Company (Strand Road) Limited | Households | 2019 |
| College View Management Company Limited | Households | 2003 |
| Collision Claims Limited | Other services | 2020 |
| Conmile Limited | Professional & scientific | 2020 |
| Connolly & Bradley Limited | Professional & scientific | 2024 |
| Coolmaghery View Management Company Ltd | Households | 2024 |
| Copperthorpe Management Services Limited | Households | 2003 |
| Coralmount Management Company Ltd | Real estate | 2018 |
| Corndale Ltd | Manufacturing | 2016 |
| Corner Bar Ireland Ltd | Hospitality | 2022 |
| Corner Bar Properties Ltd | Administrative & support | 2023 |
| Cornmill Brewery Limited | Manufacturing | 2021 |
| Corvally Holdings Limited | Financial services | 2019 |
| CR Accountancy Ltd | Professional & scientific | 2019 |
| CR Tree Services Ltd | Agriculture & fishing | 2017 |
| Cregglea Management Company Limited | Households | 2000 |
| CRF Contracts & Consulting Ltd | Construction | 2019 |
| Crossfit Limavady CIC | Arts & recreation | 2025 |
| Crossreagh | Arts & recreation | 2023 |
| Cscd Investments Limited | Real estate | 2021 |
| CSK Enterprises Ltd | Real estate | 2023 |
| Culbertsons Food Halls Limited | Wholesale & retail | 2007 |
| Culmore Energy Ltd | Energy | 2015 |
| Culmore Square Management Company Limited | Households | 2003 |
| Curif Holdings Limited | Financial services | 2016 |