| Dakota Silvan LLP | | 2017 |
| Dalco Engineering Systems NI Limited | Professional & scientific | 2014 |
| Dale Express Taxi Ltd | Transport & logistics | 2021 |
| Dale Farm Dairies Limited | Extraterritorial | 2000 |
| Dale Farm Dairy Group Limited | Extraterritorial | 2002 |
| Dale Farm Dairy Products Limited | Extraterritorial | 2002 |
| Dale Farm Foods Limited | Extraterritorial | 2002 |
| Dale Farm Gridco Ltd | Manufacturing | 2017 |
| Dale Farm Ice Cream Limited | Wholesale & retail | 1999 |
| Dale Farm Ingredients Limited | Extraterritorial | 1984 |
| Dale Farm Limited | Manufacturing | 1991 |
| Dale Health Group Ltd | Health & social care | 2026 |
| Daley Blue Ltd | Professional & scientific | 2022 |
| Daley Construction Ltd | Wholesale & retail | 2025 |
| Dalian Huide ( UK ) Ltd | Wholesale & retail | 2022 |
| Dalidali Limited | Wholesale & retail | 2025 |
| Dalj Ndsliw Ltd | Wholesale & retail | 2024 |
| Dalmarich Ltd | Wholesale & retail | 2020 |
| Dalmatia Ltd | Wholesale & retail | 2020 |
| Dalriada Trustee Company Limited | Professional & scientific | 2015 |
| Dalriada Trustees Limited | Other services | 2000 |
| Dalt Capital Ltd | Financial services | 2026 |
| Dalta Ltd | Professional & scientific | 2025 |
| Dalto Group Limited | Financial services | 2018 |
| Dalto Limited | Financial services | 2018 |
| Dalto Trading NO.1 Limited | Extraterritorial | 2018 |
| Dalto Trading NO.2 Limited | Extraterritorial | 2018 |
| Dalto Trading NO.3 Limited | Extraterritorial | 2018 |
| Dalto Trading NO.4 Limited | Extraterritorial | 2018 |
| Dalto Trading NO.5 Limited | Extraterritorial | 2018 |
| Daly & Daly Limited | Real estate | 2019 |
| Daly Makeup Limited | Other services | 2011 |
| Daly Recruitment Ltd | Administrative & support | 2025 |
| Daly's Garage Limited | Wholesale & retail | 2014 |
| Dalyan Kebabs Belfast Ltd | Hospitality | 2026 |
| Dalziel Services Ltd | Information & communication | 2026 |
| Dama (Belfast) Ltd | Hospitality | 2015 |
| Dama 1 Ltd | Hospitality | 2025 |
| Dama 2 Ltd | Hospitality | 2026 |
| Dama Construction Services Limited | Construction | 2019 |
| Dama Group Limited | Financial services | 2019 |
| Dama Land & Property NI Ltd | Real estate | 2025 |
| Damaka Property Limited | Real estate | 2026 |
| Dameom Limited | Wholesale & retail | 2023 |
| Damian Auld Ltd | Manufacturing | 2016 |
| Damien Conway Ltd | Professional & scientific | 2026 |
| Dami’S Care Limited | Public administration | 2025 |
| Dammvendingco Limited | Wholesale & retail | 2026 |
| Damp and Timber Specialists NI Ltd | Construction | 2022 |
| DAN Hughes Ltd | Wholesale & retail | 2021 |
| Danaher UK Industries (2006) Limited | | 2005 |
| Dance Industries Ltd | Extraterritorial | 2022 |
| Danescourt Management Limited | Households | 2013 |
| Danesfort Park (Carryduff) Management Company Limited | Households | 2005 |
| Danesfort Park Management Company Limited | Households | 2004 |
| Dangle Academy Ltd | Administrative & support | 2023 |
| Danhong Limited | Wholesale & retail | 2024 |
| Dani Pro Ltd | Wholesale & retail | 2025 |
| Daniel Corriga Ltd | Wholesale & retail | 2024 |
| Daniel Corrigan Ltd | Wholesale & retail | 2024 |
| Daniel Meyer Limited | Wholesale & retail | 2023 |
| Daniel P. Hale & Co. (Fruit Importers) Limited | Extraterritorial | 1975 |
| Danister Impex LP | | 2018 |
| Dannasu Ltd | Wholesale & retail | 2024 |
| Danny BOY Label LLP | | 2007 |
| Danny Kelly Limited | Wholesale & retail | 2025 |
| Danram Limited | Health & social care | 2023 |
| Dans OCT Ltd | Information & communication | 2024 |
| Dansard Management Services Ltd | Professional & scientific | 2004 |
| Dantes Food Services Limited | Hospitality | 2011 |
| Danu Media Limited | Information & communication | 2026 |
| Danube Street Management Company Limited | Extraterritorial | 2007 |
| Daphlyn Investment Limited | Real estate | 2025 |
| Dapok Limited | Real estate | 1997 |
| Daram Khola Ltd | Hospitality | 2021 |
| Darcy Logistics Limited | Transport & logistics | 2022 |
| Dardanus Limited | Real estate | 2016 |
| Dargan Chemicals Limited | Manufacturing | 2013 |
| Dargan Court Ltd. | Real estate | 1993 |
| Dargan House and Lady Pirrie Management Company Limited | Households | 2025 |
| Dargan Road Biogas Limited | Energy | 2017 |
| Dark Hedges Limited | Real estate | 2016 |
| Dark Hedges Management Ltd | Hospitality | 2019 |
| Dark Red Design Ltd | Professional & scientific | 2013 |
| Darkened Room Music Ltd | Information & communication | 2026 |
| Darker Still Spirits (NI) Limited | Wholesale & retail | 2023 |
| Darkforce Ltd | Information & communication | 2021 |
| Darko Enterprises Limited | Wholesale & retail | 2023 |
| Darkskope (Holdings) Limited | Information & communication | 2025 |
| Darkskope Intelligence Limited | Information & communication | 2025 |
| Darkskope Limited | Information & communication | 2023 |
| Darksource Group Limited | Information & communication | 2023 |
| Darmar Elite Ltd | Hospitality | 2026 |
| Darmay Khatun Ltd | Wholesale & retail | 2024 |
| Darragh Collins Architects Ltd | Professional & scientific | 2025 |
| Darren Kerr Electrical & Property Services Limited | Construction | 2023 |
| Darren Lannigan Welding Services Limited | Manufacturing | 2014 |
| Darwin Pictures Limited | Information & communication | 2026 |
| Dash Developments Ltd | Administrative & support | 2002 |
| Dashcoffeebelfast Ltd | Hospitality | 2025 |