| Don'T Box ME in Ltd | Health & social care | 2021 |
| Donnelly Industrial Holdings Ltd | Financial services | 2024 |
| Donnelly Specialist Flooring Ltd | Construction | 2019 |
| Doolin Bespoke Ltd | Manufacturing | 2021 |
| Douglas Hughes Developments Limited | Construction | 1999 |
| Douglas PM Services Ltd | Professional & scientific | 2023 |
| Down Property Ltd | Construction | 2021 |
| Downton Professional Services Limited | Financial services | 2015 |
| Doybar Limited | Real estate | 2002 |
| Doyle & Company Developments Limited | Construction | 2021 |
| DP Supermarkets Limited | Wholesale & retail | 2007 |
| DR Kealan Limited | Health & social care | 2026 |
| Dream Break Competitions Ltd | Arts & recreation | 2026 |
| DRH Builders Ltd | Construction | 2022 |
| Driftforge Solutions Ltd | Professional & scientific | 2026 |
| Drinkapp Limited | Hospitality | 2018 |
| Drop Inn Ministries Limited | Education | 2017 |
| Druids Glen Ltd | Construction | 2022 |
| Drumarg Properties Limited | Real estate | 2014 |
| Drumarg Property Services Limited | Real estate | 2014 |
| Drumcairn Holdings Limited | Administrative & support | 2011 |
| Drumgar Holdings Ltd | Financial services | 2025 |
| Drumgar Poultry Limited | Agriculture & fishing | 2015 |
| Drumgaw Farms | Agriculture & fishing | 2011 |
| Drumgola Properties Limited | Construction | 2021 |
| Drumgose Farms Limited | Agriculture & fishing | 2013 |
| Drumgreenagh Transport Limited | Transport & logistics | 2022 |
| Drumhill Property Limited | Households | 2024 |
| Drummanmore Management Company Limited | Extraterritorial | 2009 |
| Drummanmore Services Limited | Construction | 2013 |
| Drummore Groundworks Ltd | Construction | 2025 |
| DS Refrigeration Ltd | Manufacturing | 2012 |
| DSB Haulage Ltd | Transport & logistics | 2019 |
| DSS Systems Ltd | Administrative & support | 2017 |
| DTH Property Limited | Real estate | 2022 |
| DTW Property Management Limited | Real estate | 2024 |
| Ductfab Fabrications NI Limited | Manufacturing | 2025 |
| Duggan Property Developments Ltd | Construction | 2017 |
| DUN Beag Investments Ltd | Real estate | 2022 |
| Dunarm Limited | Real estate | 2004 |
| Dundrum Enterprises Ltd | Real estate | 2021 |
| Dundrum Tassagh Ltd | Financial services | 2022 |
| Dunlarg Builders Limited | Construction | 2016 |
| Dunlarg Holdings Ltd | Real estate | 2021 |
| Dunluce Recruitment Ltd | Hospitality | 2019 |
| Duoform Limited | Wholesale & retail | 2025 |
| Durand & Harau Ltd | Information & communication | 2026 |
| Dynes Bros Ltd | Construction | 2016 |
| E Treads Limited | Manufacturing | 2020 |
| E. Mallon Motors Ltd | Wholesale & retail | 2013 |
| E.D.G.E Fitness & Performance Ltd | Arts & recreation | 2019 |
| Earlybird Playgroup | Education | 2000 |
| Easy Safety Signs (NI) Limited | Manufacturing | 2025 |
| Eblana Enterprise Group (NI) Limited | | 1997 |
| Echo Gecko Limited | Mining & quarrying | 2014 |
| Ecommerce Specialists Ltd | Information & communication | 2022 |
| Eddie's Kitchen Ltd | Hospitality | 2020 |
| Edelweiss NI Ltd | Wholesale & retail | 2022 |
| Eden Co (N.I) Ltd | Wholesale & retail | 2025 |
| Eden Construction (N.I.) Ltd | Construction | 2018 |
| Eden Decorators Limited | Wholesale & retail | 1998 |
| Edengrow Farms Limited | Agriculture & fishing | 2013 |
| Edenveagh Limited | Professional & scientific | 2017 |
| EDF Tile and Stone Contracts Ltd | Wholesale & retail | 2025 |
| EF Recovery Ltd | Manufacturing | 2016 |
| EG Contracts Ltd | Construction | 2019 |
| Eimear Mullen Brows & Beauty Ltd | Other services | 2021 |
| Electro Trade Limited | Wholesale & retail | 2024 |
| ELH Rental Property Ltd | Real estate | 2020 |
| Elmore Tyre Recycling Ltd | Wholesale & retail | 2024 |
| Emain Publications Limited | Information & communication | 2012 |
| Emcp Limited | Health & social care | 2019 |
| Emerald Automotive Assessors Ltd | Professional & scientific | 2025 |
| Emerald Leap Ltd | Arts & recreation | 2024 |
| Emerald Shipping Ltd | Transport & logistics | 2025 |
| Emko Industrial NI Limited | Wholesale & retail | 2024 |
| Empower (N.I.) Limited | Arts & recreation | 2019 |
| Enagh 2 Ltd | Professional & scientific | 2014 |
| Enagh Contractors Ltd | Real estate | 2017 |
| Enagh HD Limited | Construction | 2019 |
| Enagh Holdings Ltd | Construction | 2018 |
| Enagh Investments Limited | Real estate | 2011 |
| Enagh Property Development Ltd | Construction | 2019 |
| Enagh Transport Ltd | Extraterritorial | 2015 |
| Enercon ECV Ltd | Construction | 2017 |
| Energy Tech (NI) Ltd | Construction | 2014 |
| Engcon Services Ltd | Professional & scientific | 2024 |
| Engineer for Hire Ltd | Professional & scientific | 2026 |
| Ennislare Farm Limited | Agriculture & fishing | 2025 |
| Epic Sales & Marketing Ltd | Professional & scientific | 2025 |
| Equal and Right Recruitment Limited | Administrative & support | 2018 |
| Ergocrafts Ltd | Wholesale & retail | 2025 |
| Eringold Enterprises Limited | Wholesale & retail | 1993 |
| ERO Trading Limited | Construction | 2011 |
| ESM Farms Ltd | Agriculture & fishing | 2023 |
| ETS Control Systems Limited | Manufacturing | 2014 |
| Eurailpackages Limited | Administrative & support | 2018 |
| Evcore Ltd | Construction | 2025 |
| Eveson Toys (N.I.) Limited | Transport & logistics | 2004 |
| Evolve Consulting Partners Ltd | Professional & scientific | 2024 |