| Revilo HQ Ltd | Administrative & support | 2025 |
| Rexl Ltd | Information & communication | 2022 |
| Rghd Investments Limited | Real estate | 2023 |
| RHM Commercial LLP | | 2007 |
| Rhubarb Consulting Ltd | Professional & scientific | 2022 |
| Richmond Nursing Homes Limited | Health & social care | 1988 |
| Richmond Wealth & Investment Limited | Financial services | 2017 |
| Richmond Wealth AI LLP | | 2026 |
| Richmond Wealth Group Limited | Financial services | 2022 |
| Riddall Limited | Information & communication | 2017 |
| Ringland Group Design Ltd | Construction | 2025 |
| Riverside Management Company (NI) Four Limited | Households | 2007 |
| Riverside Management Company (NI) Limited | Households | 2007 |
| Riverside Management Company (NI) One Limited | Households | 2007 |
| Riverside Management Company (NI) Three Limited | Households | 2007 |
| Riverside Management Company (NI) Two Limited | Households | 2007 |
| Rivin Leisure Limited | Hospitality | 2021 |
| RKW Orthopaedics Ltd | Health & social care | 2013 |
| RMB Cars Ltd | Wholesale & retail | 2019 |
| Robert Jamison Architects & Associates Limited | Professional & scientific | 2019 |
| Rock Ryan House Limited | Real estate | 2018 |
| Rockford Investments Limited | Real estate | 2016 |
| Rockport School Limited | Hospitality | 1967 |
| Rodgers and Browne Ltd | Extraterritorial | 2019 |
| Ronsard Ltd | Extraterritorial | 2012 |
| Roofing Express Limited | Wholesale & retail | 2025 |
| Rosemary Street Limited | Real estate | 2024 |
| Rosolas Pharma Ltd | Professional & scientific | 2025 |
| Ross's Mill Management Company Limited | Households | 2006 |
| Rossoverde Limited | Wholesale & retail | 2019 |
| Rosstulla Management Company Limited | Households | 2002 |
| Rowan Patrick Investments Ltd | Real estate | 2026 |
| Roycroft Interiors Limited | Manufacturing | 2014 |
| Roycroft Manufacturing Ltd | Manufacturing | 2020 |
| RS Cutting Edge Holdings Ltd | Professional & scientific | 2015 |
| RS Cutting Edge Qwube Ltd | Professional & scientific | 2019 |
| RSN Investments Ltd | Real estate | 2024 |
| RT Property (N.I.) Limited | Other services | 2022 |
| Rubicon Consultancy Services Limited | Real estate | 2017 |
| Rufflemouse Limited | Manufacturing | 2024 |
| Rugby Court Management Company Limited | Households | 2001 |
| Ryan Diver Photography Limited | Professional & scientific | 2019 |
| S & J Dobbs Ltd | Health & social care | 2008 |
| S & ST Holdings Ltd | Financial services | 2019 |
| S Bryans Holdings Limited | Construction | 2017 |
| S N Brand Builder Ltd | Wholesale & retail | 2024 |
| S.A.P.T. Developments Ltd | Construction | 2005 |
| S.S. Aerostar Ltd | Professional & scientific | 2014 |
| Salween Investments Limited | Financial services | 2021 |
| Sam's YER MAN Ltd | Construction | 2015 |
| Samhonora Limited | Real estate | 2020 |
| Sato Properties Ltd | Real estate | 2015 |
| Saul and Pearson Holdings Limited | Hospitality | 2016 |
| SAY IT Louder Ltd | Information & communication | 2024 |
| SC Living Ltd | Construction | 2019 |
| Sccmep EOT Limited | Extraterritorial | 2025 |
| Scofo Ltd | Wholesale & retail | 2025 |
| Seamus Investments Limited | Real estate | 2017 |
| Seapark Limited | Households | 1988 |
| Second Ravenhill Reach Management Limited | Households | 1995 |
| Second Unit Pictures Ltd | Information & communication | 2025 |
| Seen Dance Company | Arts & recreation | 2023 |
| Selskar Ltd | Information & communication | 2011 |
| SEM Aesthetics Limited | Other services | 2023 |
| Sestina (N.I.) Limited | Professional & scientific | 2016 |
| SGM Interim Solutions Limited | Professional & scientific | 2019 |
| SGS Yarsley International Certification Services Ltd | | 1994 |
| SH Podiatry Ltd | Health & social care | 2024 |
| Shaman Films Ltd | Information & communication | 2026 |
| Shankeltons Limited | Wholesale & retail | 2026 |
| Sharchris Ltd | Health & social care | 2023 |
| Sharon Radcliffe Holdings Limited | Financial services | 2015 |
| Shaw Infection Services Ltd | Health & social care | 2026 |
| SHC Property Ltd | Real estate | 2019 |
| Shore Financial Limited | Financial services | 2025 |
| Shore Road 18 Management Company Limited | Households | 2024 |
| Sicuro Consultancy Limited | Administrative & support | 2019 |
| Sidhe Films Ltd | Information & communication | 2023 |
| Silentium 7 Ltd. | Construction | 2011 |
| Silverback Weather and Emergency Solutions Ltd | Financial services | 2024 |
| Silverstream Farm Management Company Ltd | Households | 2018 |
| Silverwood Business Park Limited | Real estate | 2008 |
| Silverwood Property Developments Limited | Professional & scientific | 2005 |
| Silverwood Property Developments LLP | | 2009 |
| Sixmile Developments Limited | Real estate | 2004 |
| Sixmile Properties Ltd | Construction | 1998 |
| Sixteen South Group Limited | Information & communication | 2020 |
| Sixteen South Originals Limited | Information & communication | 2019 |
| Sixteen South Rights Limited | Information & communication | 2015 |
| Sixteen South Studios Limited | Information & communication | 2007 |
| Sleepy Hollow Holdings Limited | Financial services | 2023 |
| Smart-Ventilation Ltd | Manufacturing | 2016 |
| SMT Management Ltd | Extraterritorial | 2011 |
| Social Media Excellence Awards Limited | Administrative & support | 2019 |
| Solitaire ENT. Ltd | Real estate | 2026 |
| Solutions (Weight Management by Julianne) Limited | Health & social care | 2023 |
| Sonnet Property Ltd | Real estate | 2026 |
| SOS N.I. | Health & social care | 2006 |
| South Parade Belfast Management Company Limited | Households | 2003 |
| Southport Topco Limited | Financial services | 2020 |