| Rathdaniel Holdings Ltd | Financial services | 2020 |
| Rathgael Furnishings Limited | Manufacturing | 2014 |
| Rathowen Contracts (Ireland) Limited | Construction | 2008 |
| Raymac Kitchens Limited | Manufacturing | 2017 |
| RB Joinery & Carpentry Limited | Construction | 2016 |
| RBF Cosmetics Ltd | Wholesale & retail | 2025 |
| RBI Developments Ltd | Real estate | 2018 |
| RC Electrical Ltd | Construction | 2016 |
| RC Morris Consulting Ltd | Information & communication | 2023 |
| RCO Investments Ltd | Real estate | 2025 |
| RCQ Farms Ltd | Agriculture & fishing | 2025 |
| Rcs-Imex IRL Limited | Transport & logistics | 2025 |
| RD Dent and Aesthetics Ltd | Health & social care | 2025 |
| RDF1 Investments Ltd | Real estate | 2025 |
| Rebox Ltd | Wholesale & retail | 2025 |
| Reclain Contracts Ireland Ltd | Construction | 2021 |
| Reclain Contracts Ltd | Transport & logistics | 2011 |
| Reclain Limited | Professional & scientific | 2021 |
| Recon Compliance Limited | Real estate | 2023 |
| Recon Renewables Ltd. | Construction | 2021 |
| Recro Engineering Ltd | Manufacturing | 2009 |
| Recruit Asap Limited | Administrative & support | 2024 |
| Recruitment Partnership (UK & Ireland) Ltd | Administrative & support | 2023 |
| Red 1 Engineering Ltd | Manufacturing | 2023 |
| Red DOT Publications Ltd | Information & communication | 2013 |
| Redcherry Bidco Limited | Financial services | 2021 |
| Redford Industrial Ltd | Manufacturing | 2023 |
| Redridge Software Ltd | Information & communication | 2026 |
| Reen Engineering Ltd | Professional & scientific | 2021 |
| Reenaderry Transport Ltd | Extraterritorial | 2010 |
| Reenafarm Organics TA the Soil MAN Ltd | Agriculture & fishing | 2014 |
| Reenpro Ltd | Professional & scientific | 2016 |
| Rehabstudio Ltd | Information & communication | 2005 |
| Reid Construction (Cookstown) Limited | Construction | 2022 |
| Reid Group Holdings Limited | Financial services | 2024 |
| Relough Holsteins Ltd | Agriculture & fishing | 2010 |
| Renovar Carbon Ltd | Professional & scientific | 2023 |
| Rent Sorted Limited | Real estate | 2022 |
| REP Technology Ltd | Manufacturing | 2020 |
| Restore Manage Consult (NI) Ltd | Construction | 2023 |
| Restwell Manufacturing Ltd | Wholesale & retail | 2016 |
| Reussite Group Ltd | Professional & scientific | 2025 |
| RGC (Holdings) Ltd | Financial services | 2019 |
| RGE Limited | Real estate | 2015 |
| RGF2 Investments Ltd | Real estate | 2025 |
| RH Fleet Ltd | Wholesale & retail | 2025 |
| Rhoalan Transport Ltd | Transport & logistics | 2013 |
| Rhone Transport Ltd | Transport & logistics | 2020 |
| RI & MA Hamilton Ltd | Agriculture & fishing | 2024 |
| Richmount Ltd | Hospitality | 2020 |
| Ringmor Properties Limited | Construction | 2003 |
| Rising Comedy Ltd | Arts & recreation | 2024 |
| Rising Music Ltd | Professional & scientific | 2018 |
| Rising PR Ltd | Professional & scientific | 2017 |
| Rising Promotions Ltd | Other services | 2023 |
| River Tall Productions Ltd | Arts & recreation | 2021 |
| Riverside Civils Ltd | Construction | 2019 |
| Riverside Developments Ireland Ltd | Real estate | 2025 |
| RJ Carolan Fire Engineering Ltd | Professional & scientific | 2025 |
| RJ Welfare Ltd | Administrative & support | 2023 |
| Rjmcivor Ltd | Real estate | 2025 |
| RK Motors (NI) Limited | Agriculture & fishing | 2009 |
| RLA (N.I.) Ltd | Administrative & support | 2010 |
| RM Dungannon Ltd | Manufacturing | 2004 |
| RM Leisure Limited | Arts & recreation | 2017 |
| RM Properties Ireland Limited | Real estate | 2025 |
| RM Trade Sales (Eglish) Ltd | Wholesale & retail | 2022 |
| RM Tyres (Eglish) Ltd | Wholesale & retail | 2018 |
| RMA Industries Ltd | Manufacturing | 2023 |
| RMC Utilities Ltd | Information & communication | 2018 |
| Rmjb Holdings Ltd | Professional & scientific | 2014 |
| RMK Bathrooms Ltd | Construction | 2022 |
| RMR Contracts Ltd | Manufacturing | 2018 |
| RNS Leisure Ltd | Hospitality | 2018 |
| Road Safety Audit Consultants Limited | Professional & scientific | 2012 |
| Roan Groundworks Ltd | Construction | 2017 |
| Roan Lifting Services Ltd | Transport & logistics | 2023 |
| Roan Systems Limited | Construction | 2020 |
| Robert Capper Holdings Limited | Professional & scientific | 2012 |
| Rock 30 Holdings Limited | Manufacturing | 2023 |
| Rock Renewables Limited | Professional & scientific | 2013 |
| Rockroland Ltd. | Information & communication | 2005 |
| Rogha Ltd | Professional & scientific | 2023 |
| ROL Testing Limited | Construction | 2010 |
| Romac Contracts Ltd | Construction | 2018 |
| Romany Interpreting & Translations Ltd | Wholesale & retail | 2023 |
| Ronoc Contracts Ltd | Construction | 2019 |
| Roof Guard CS Limited | Construction | 2025 |
| Roof Protection & Landscaping Limited | Construction | 2026 |
| Roofing Shield Ltd | Construction | 2026 |
| Rosehill 5 Ltd | Hospitality | 2026 |
| Roseholl Ltd | Hospitality | 2024 |
| Roughan Care Ltd | Health & social care | 2010 |
| Roughan Legal Limited | Professional & scientific | 2024 |
| Roundwood Engineering Works Limited | Professional & scientific | 2015 |
| Rowan Equestrian and Country Store Ltd | Wholesale & retail | 2022 |
| Rowan RUA Ltd | Financial services | 2024 |
| Roxborough Ground Improvement Ltd | Construction | 2021 |
| Roxborough Plant & Construction Ltd | Construction | 2012 |
| Roxy SAS Holdings Limited | Real estate | 2016 |