| 100 Accurate Co VID Tests Ltd | Extraterritorial | 2021 |
| 3 Amigos Deli Ltd | Hospitality | 2023 |
| 365 Fire Security Ltd | Construction | 2022 |
| AB Plant Services Ltd | Professional & scientific | 2021 |
| Adrian Grant Commercials Ltd | Wholesale & retail | 2017 |
| Advanced Polymer Coatings Limited | Manufacturing | 2020 |
| Aerospike Systems Ltd | Wholesale & retail | 2024 |
| Agri Spec Ltd | Manufacturing | 2025 |
| Aiken Consulting Limited | Professional & scientific | 2015 |
| Airport Road Cafe Ltd | Hospitality | 2014 |
| Airtread Ltd | Professional & scientific | 2026 |
| Aldamar (NO.1) Limited | Water & waste | 2024 |
| Aldamar Holdings Ltd | Water & waste | 2017 |
| Aldergrove Contracts Limited | Construction | 2024 |
| Aldergrove Cottage Ltd | Hospitality | 2021 |
| Aldergrove House of Prayer | Other services | 2005 |
| ALL Clear N.I Limited | Water & waste | 2025 |
| Altais Digital Ltd | Information & communication | 2009 |
| AMC Weddings Ltd | Arts & recreation | 2021 |
| AMG Weldall Ltd | Manufacturing | 2025 |
| AN1 Plumbing & Heating Ltd | Construction | 2024 |
| Ankar CIC | Health & social care | 2025 |
| Antrim Agri-Fertilizer Ltd | Real estate | 2011 |
| Antrim Agricultural Society | Information & communication | 1960 |
| Antrim Coal Company Limited | Extraterritorial | 1985 |
| Antrim Farming Limited | Real estate | 2012 |
| Antrim Playball Ltd | Education | 2019 |
| Apex Executive Transport Limited | Transport & logistics | 2025 |
| APM1992 Ltd | Real estate | 2021 |
| Aqua Developments Limited | Construction | 2000 |
| Aqua Marine Developments Limited | Agriculture & fishing | 2002 |
| Aquarius Couriers Ltd | Transport & logistics | 2014 |
| AR Crumlin Ltd | Manufacturing | 2025 |
| Ardowen Ltd | Extraterritorial | 2023 |
| ASD Freight Limited | Transport & logistics | 2016 |
| Ashfield & Wilson Ltd | Wholesale & retail | 2005 |
| Asian Taste Glenavy Ltd | Hospitality | 2026 |
| ASK NI Properties Ltd | Real estate | 2023 |
| Atob Consultant Ltd | Professional & scientific | 2023 |
| Autoboland NI Ltd | Wholesale & retail | 2023 |
| Autocult.Ni Ltd | Wholesale & retail | 2022 |
| Autonuts Ltd | Wholesale & retail | 2023 |
| Awaywalkies Limited | Agriculture & fishing | 2024 |
| Axis Fibre Solutions Limited | Information & communication | 2023 |
| B Price Quality Meats Limited | Wholesale & retail | 2020 |
| BAD Brain Productions Ltd | Information & communication | 2024 |
| Bagwl 368 Ltd | Wholesale & retail | 2025 |
| Ballyhill Trading Limited | Manufacturing | 2021 |
| Ballymather Estates Ltd | Real estate | 2013 |
| BCH LOG Cabin Retreat Ltd | Hospitality | 2026 |
| Beattie Fitness Ltd | Arts & recreation | 2020 |
| Belfast Canopy Ltd | Professional & scientific | 2025 |
| Belfast Pet Supplies Ltd | Wholesale & retail | 2025 |
| Bemac Training Ltd | Administrative & support | 2002 |
| BF Mulholland Limited | Wholesale & retail | 2011 |
| BFL Services Limited | Manufacturing | 2004 |
| Black Mountain Assets Ltd | Real estate | 2022 |
| Black Sheep (Social Enterprise) CIC | Administrative & support | 2023 |
| Boltnaconnel Holdings Ltd | Real estate | 2024 |
| Boxing Hare Foods Ltd | Hospitality | 2026 |
| Brooks Auto Repair N.I. Ltd | Wholesale & retail | 2025 |
| Brothers Restaurants Crumlin Ltd | Hospitality | 2024 |
| Bushes Home Bakery Limited | Manufacturing | 2021 |
| C & S Coffee Ltd | Hospitality | 2023 |
| C Irvine & Sons Agri and Plant Hire Limited | Agriculture & fishing | 2023 |
| C Mahoney Ltd | Construction | 2020 |
| C&R Electrical Services Ltd | Construction | 2023 |
| Calgary Consultancy Ltd | Extraterritorial | 2020 |
| Cards Galore Belfast Limited | Wholesale & retail | 2003 |
| Carey Vertex Ltd | Professional & scientific | 2024 |
| Carl Medical Ltd | Health & social care | 2022 |
| Carlton PCM Ltd | Extraterritorial | 2020 |
| Causeway Vision Limited | Wholesale & retail | 2012 |
| CD Utilities Ltd | Construction | 2026 |
| Cedar Design Management Limited | Professional & scientific | 2021 |
| Celtic Food Products Limited | Wholesale & retail | 2009 |
| Certcom Training Limited | Transport & logistics | 2025 |
| CGC Weddings Ltd | Arts & recreation | 2022 |
| Charlie's DEN Ltd | | 2012 |
| CHP Solutions Ireland Ltd | Manufacturing | 2022 |
| Chris Robb Aviation Services Ltd | Transport & logistics | 2022 |
| Cider Road Properties Ltd | Real estate | 2024 |
| Cidercort 1416 Limited | Households | 2025 |
| CIP Insurance Brokers Ltd | Financial services | 2009 |
| CIP Insurance Holdings Ltd | Financial services | 2009 |
| CJH Coffee Ltd | Hospitality | 2026 |
| CM Direct Online Ltd | Wholesale & retail | 2023 |
| CMC Consulting (N.I.) Ltd | Professional & scientific | 2021 |
| CMG Collaborations Ltd | Real estate | 2024 |
| Coiste Ghaeloideachas Chromghlinne (CGC) | Education | 2011 |
| Colinglen Construction Ltd | Construction | 2016 |
| Colinglen Inns Ltd | Hospitality | 2023 |
| Commercial Medical Cleaning LLP | | 2018 |
| Cone Construction Limited | Construction | 2011 |
| Connery Contracts Ltd | Construction | 2021 |
| Cormican (Ireland) Ltd. | Transport & logistics | 2013 |
| Cosaint Training & Consultancy Ltd | Education | 2016 |
| Coval Developments Limited | Construction | 2015 |
| CPC Weddings Ltd | Arts & recreation | 2022 |
| Creaney Investments Limited | Real estate | 2025 |