| Dmacm Limited | Professional & scientific | 2022 |
| DMC Engineering N.I. Ltd | Construction | 2025 |
| Dmckeown Hiab Hire Ltd | Transport & logistics | 2025 |
| DMK Draughting Services Ltd | Professional & scientific | 2019 |
| DMW Entertainments Ltd | Information & communication | 2026 |
| DNS (NI) Limited | Professional & scientific | 2010 |
| Doll Face - House of Makeup Ltd | Arts & recreation | 2016 |
| Donmac Farms Ltd | Agriculture & fishing | 2002 |
| Donna Donaghy Skincare & Laser Ltd | Health & social care | 2019 |
| Donnelly Property Solutions Ltd | Real estate | 2025 |
| DR Trading (NI) Ltd | Wholesale & retail | 2018 |
| DR Waqar Ltd | Health & social care | 2025 |
| Drapersfield Ltd | Health & social care | 2015 |
| Dream Desserts N.I. Limited | Hospitality | 2024 |
| Drumbrick Wind Ltd | Energy | 2013 |
| Drumco Ltd | Financial services | 2025 |
| Drumcrin Enterprises Ltd | Financial services | 2024 |
| Drumlegagh Wind Ltd | Energy | 2014 |
| DS Interior Specialists Limited | Construction | 2021 |
| DSL Bars Ltd | Hospitality | 2018 |
| DSL Leisure Events Ltd | Hospitality | 2020 |
| Duct Services (N.I.) Ltd | Energy | 2011 |
| Dungannon Motor Club, Limited | Arts & recreation | 1961 |
| Dungate Management Limited | Professional & scientific | 2012 |
| Dunleath NI Ltd | Hospitality | 2013 |
| Dunman Fuels Ltd | Wholesale & retail | 2017 |
| DW Haulage Ltd | Transport & logistics | 2018 |
| Dynamic Origin Ltd | Information & communication | 2023 |
| Dynes and Sons Limited | Financial services | 2022 |
| E P H Construction Ltd | Construction | 2016 |
| E&Y Turkish Barber Ltd | Other services | 2026 |
| E.K.S. Tyres (NI) Limited | Manufacturing | 1978 |
| Eagle Shelf Company Limited | Financial services | 2019 |
| Eagles View Ltd | Financial services | 2025 |
| Eagleson's Farm Ltd | Energy | 2014 |
| Eamonn Moore Architect Ltd | Professional & scientific | 2019 |
| East Sperrin Fabrication Limited | Professional & scientific | 2017 |
| Easy Go Transport Ltd | Transport & logistics | 2016 |
| EBQ Engineering Limited | Construction | 2026 |
| ECA MID Ulster Limited | Education | 2025 |
| Ecoloc Ltd | Construction | 1996 |
| ED Fire & Consultancy Ltd. | Professional & scientific | 2015 |
| Eddie Corr Racing Ltd | Professional & scientific | 2008 |
| Eddie's PUB Greencastle Ltd | Hospitality | 2023 |
| EDT Groundworks Ltd | Construction | 2025 |
| Edward Group Limited | Real estate | 2015 |
| EG Accountancy Services Ltd | Professional & scientific | 2021 |
| EG Consultancy Ltd | Professional & scientific | 2024 |
| Eirefab Ltd | Manufacturing | 2026 |
| Ejjts Ltd | Real estate | 2021 |
| EK Studio Ltd | Professional & scientific | 2023 |
| EL18 Limited | Extraterritorial | 2024 |
| Elagh Properties Ltd | Households | 2016 |
| Elder Heights Company Limited | Real estate | 2020 |
| Elder Terrace Company Limited | Real estate | 2020 |
| Electronic Scoreboard Units Ltd | Manufacturing | 2005 |
| Eled Legal Consulting Limited | Professional & scientific | 2015 |
| Elite Performance Solutions Ireland Ltd | Arts & recreation | 2025 |
| Elite Physiotherapy Limited | Health & social care | 2021 |
| Elite World Travel NI Ltd | Administrative & support | 2019 |
| ELM Heights Company Limited | Extraterritorial | 2015 |
| Elqd Ecigs Ltd | Wholesale & retail | 2018 |
| Emboe Energy Ltd. | Energy | 2017 |
| Embroiderus Ireland Ltd | Professional & scientific | 2010 |
| Emily's Coffee Bar Ltd | Hospitality | 2012 |
| EML DOR 1 Limited | Construction | 2022 |
| EML Dunmurry Lane Limited | Real estate | 2023 |
| EML GNT Enterprises Limited | Financial services | 2021 |
| EML Holdings Limited | Extraterritorial | 2021 |
| EML Investments Limited | Financial services | 2021 |
| EML Property Investments Limited | Extraterritorial | 2021 |
| EML Rathger Holdings Limited | Financial services | 2025 |
| EML ROI Resi Limited | Professional & scientific | 2013 |
| Empire Events (N.I.) Ltd | Other services | 2016 |
| Enably Ltd | Information & communication | 2026 |
| Energex (IRL) Ltd | Wholesale & retail | 2025 |
| Energex 365 Ltd | Wholesale & retail | 2023 |
| Energy Mind and Body Limited | Health & social care | 2019 |
| Engineering Plastics Limited | Manufacturing | 2001 |
| Enhance IT Systems Ltd | Wholesale & retail | 2016 |
| Enisca Browne Limited | Water & waste | 2015 |
| Enisca Group Limited | Financial services | 2017 |
| Enisca Limited | Water & waste | 1999 |
| Enisca Site Services Limited | Water & waste | 2017 |
| EON Chatel Limited | Real estate | 2022 |
| EPD QS Solutions Ltd | Professional & scientific | 2007 |
| ES Bedford Street Limited | Real estate | 2013 |
| ES Beechmount Holdings Limited | Financial services | 2022 |
| ES Blackparks Limited | Financial services | 2022 |
| ES Brunswick Limited | Extraterritorial | 2010 |
| ES City Square Limited | Extraterritorial | 2011 |
| ES College Court Limited | Extraterritorial | 2011 |
| ES Corporation Street Limited | Real estate | 2011 |
| ES DOR 10 Limited | Professional & scientific | 2018 |
| ES DOR 24 Limited | Extraterritorial | 2024 |
| ES Enterprise Holdings Limited | Financial services | 2021 |
| ES Manchester High Limited | Real estate | 2021 |
| ES Newgate Limited | Real estate | 2011 |
| ES Newtownards Limited | Construction | 2006 |
| ES Ruanbeg Limited | Financial services | 2022 |