| DU Holdings Ltd | Financial services | 2025 |
| Dubbleclix Ltd | Information & communication | 2025 |
| Duckpondni Ltd | Hospitality | 2021 |
| Dufferin Hall | Other services | 2023 |
| Duframe Lkui Limited | Wholesale & retail | 2025 |
| Dukes Belfast LLP | | 2007 |
| Dumb Luck Coffee Ltd | Manufacturing | 2026 |
| Dumpling Library (Newcastle) Ltd | Hospitality | 2022 |
| Dunaskin Student Limited | Construction | 2013 |
| Dunbeag Farm Ltd | Agriculture & fishing | 2025 |
| Duncan House Developments Limited | Construction | 2015 |
| Duncan Sheds Ltd | Construction | 2025 |
| Duncrue Holdings Ltd | Financial services | 2022 |
| Duncrue Property Ltd | Real estate | 2022 |
| Dunlop Automotives Limited | Manufacturing | 2007 |
| Dunlop Building Group Limited | Construction | 2018 |
| Dunlop Developments Limited | Real estate | 1991 |
| Dunlop Enterprises Group Ltd | Professional & scientific | 2015 |
| Dunlop Group Limited | Real estate | 2018 |
| Dunlop Hawe Ltd | Real estate | 2022 |
| Dunlop Property Management Ltd | Real estate | 1972 |
| Dunlop Trading Ltd | Wholesale & retail | 2015 |
| DWB Rentals Ltd | Real estate | 2025 |
| DWR Cerist CYF | Wholesale & retail | 2009 |
| Dwyfor Environmental Limited | Professional & scientific | 2015 |
| DÀ Boba Ltd | Wholesale & retail | 2023 |
| E R J Handtools Limited | Manufacturing | 2004 |
| E.R. LEE Limited | Transport & logistics | 2012 |
| Eagle Wing Developments Ltd | Construction | 2026 |
| Early Days Pre-School (Bangor) Ltd | Education | 2021 |
| Early Intervention Wales Training Limited | Education | 2004 |
| Earth Rainbow Limited | Manufacturing | 2019 |
| East Cottage Estates Limited | Real estate | 2015 |
| Eastern Dental Laboratory Limited | Health & social care | 2011 |
| Eastern Diamond Back Ltd | Professional & scientific | 2025 |
| EAT Group Ltd | Hospitality | 2015 |
| Eat&Co Ltd | Hospitality | 2021 |
| Eblana Real Estate Ltd | Real estate | 2014 |
| ECC Investments Limited | Financial services | 2025 |
| Eclg Collective Ltd | Wholesale & retail | 2024 |
| Eco Energy Homes Ltd | Professional & scientific | 2014 |
| Eco Render Ltd | Construction | 2022 |
| Ecoheat Renewable Energy Ltd | Construction | 2024 |
| Ecoleg Eryri CYF. | Professional & scientific | 2026 |
| Ecolodge Limited | Extraterritorial | 2007 |
| Ecoutility Energy Limited | Administrative & support | 2008 |
| Eddie Fulton Management Solutions Limited | Professional & scientific | 2017 |
| Eddie Trading Ltd | Hospitality | 2020 |
| Edith & George Limited | Wholesale & retail | 2018 |
| Edmonds Aero Limited | Professional & scientific | 2024 |
| Edoc Deposit Limited | Information & communication | 2011 |
| EEC Electronics Limited | Professional & scientific | 2016 |
| Efficusai Ltd | Information & communication | 2025 |
| EG Developments (Bangor) Ltd. | Real estate | 2017 |
| Egniol Construction Services Limited | Construction | 2026 |
| Egniol Consulting Limited | Water & waste | 2008 |
| Egniol Planning Limited | Professional & scientific | 2024 |
| EH & AB Properties Ltd | Real estate | 2024 |
| Eiddo Carnen CYF | Real estate | 2025 |
| Eiddo Zyborski CYF | Real estate | 2026 |
| EK 68 Ltd | Hospitality | 2016 |
| EK Commercial Solutions Limited | Transport & logistics | 2019 |
| EKO Sweet Organic Candies Limited | Wholesale & retail | 2025 |
| EL Ministries International | Other services | 2023 |
| Eladon Limited | Construction | 1990 |
| Elancare Studio Limited | Other services | 2025 |
| Electricbuilders Ltd | Construction | 2025 |
| Electro Fishing Services Ltd | Agriculture & fishing | 2007 |
| Elegantly Ever After Ltd | Health & social care | 2024 |
| Elevenses Distillery Ltd | Manufacturing | 2022 |
| Elira Solutions Ltd | Professional & scientific | 2025 |
| Elite Consulting N.I. Limited | Administrative & support | 2013 |
| Elite Corporate Investments Limited | Professional & scientific | 2020 |
| Elite Essentials Limited | Wholesale & retail | 2025 |
| Elizabeth a Mcfarland Ltd | Other services | 2025 |
| Elizabeth Bradley Design (2006) Limited | Manufacturing | 2006 |
| Ellen Street Hove Limited | Construction | 2019 |
| Ellesmere Renewables Ltd | Energy | 2011 |
| Elliott Road Selly Oak Limited | Construction | 2018 |
| Eluxury Ltd | Wholesale & retail | 2025 |
| Elwood James Ltd | Real estate | 2024 |
| Embyd Global Ventures Ltd | Wholesale & retail | 2026 |
| Emcm Developments Ltd | Households | 2025 |
| Emery Quinn Limited | Professional & scientific | 2023 |
| Emos Infineer Limited | Extraterritorial | 2010 |
| Empirical Financial Planning LLP | | 2026 |
| EMX Group Ltd | Construction | 2026 |
| Energy (NI) Ltd | Professional & scientific | 2008 |
| Energy Local CIC | Professional & scientific | 2016 |
| Enfys Ecology Limited | Professional & scientific | 1990 |
| Enhanced Aesthetics & Lashes Ltd | Other services | 2024 |
| Ensemble Cymru | Arts & recreation | 2001 |
| Enstor Ltd | Professional & scientific | 2022 |
| Enterprise Business Review NI CIC | Information & communication | 2026 |
| Enterprise Road Management Company Limited | Households | 2024 |
| Entourage Athletics Ltd | Arts & recreation | 2025 |
| Environmental Training Solutions Ltd | Professional & scientific | 2019 |
| Envision Programme Management Ltd | Professional & scientific | 2023 |
| Epaod CYF | Extraterritorial | 2025 |
| Epic PR CYF | Professional & scientific | 2019 |