| Positive Attractions Limited | Information & communication | 2020 |
| Power Booker Limited | Energy | 2019 |
| PP Developments (N.I.) Ltd | Construction | 2022 |
| Premier Electrical (NI) Limited | Construction | 1997 |
| Premier Electrical Group Limited | Construction | 2018 |
| Premier Renewable Energy Holdings Limited | Financial services | 2023 |
| Premier Renewables (NI) Limited | Professional & scientific | 2011 |
| Premier Traffic Systems Limited | Transport & logistics | 2019 |
| Pro-Optimise Engineering Limited | Professional & scientific | 2023 |
| Product Megaphone Ltd | Professional & scientific | 2025 |
| Project Ballynahinch Limited | Health & social care | 2024 |
| Proven Energy Solutions Ltd | Manufacturing | 2013 |
| Pure Catering Ltd | Hospitality | 2023 |
| Quietpath Ltd | Transport & logistics | 2026 |
| Quinn Property Sales Ltd | Real estate | 2010 |
| R Macleod Properties Ltd | Construction | 2026 |
| R Savage & Co Ltd | Professional & scientific | 2011 |
| Raalex Ltd | Real estate | 2025 |
| Rackspec Limited | Manufacturing | 2010 |
| Reain-Adair Holdings Ltd | Real estate | 2024 |
| Reap (IRE) Ltd | Information & communication | 2024 |
| Red Brick Road Productions Ltd | Arts & recreation | 2013 |
| Red FOX Ltd | Professional & scientific | 2023 |
| Reid Court Management Company Limited | Real estate | 2011 |
| Reid Feeds Limited | Manufacturing | 2017 |
| Reltec (UK) Limited | | 1998 |
| Renew a Roof Ltd | Construction | 2019 |
| Right Revenue Limited | Information & communication | 2016 |
| Ritchie & Mclean Mortgage Solutions Ltd | Financial services | 2026 |
| Rivara Design Ltd | Wholesale & retail | 2026 |
| RJS Consult Construct Ltd | Construction | 2013 |
| RMK Health IS Wealth Ltd | Health & social care | 2024 |
| RNN Communications Ltd | Administrative & support | 2012 |
| Rockincolour Ltd | Mining & quarrying | 2016 |
| Rockpit Fitness Downpatrick Limited | Arts & recreation | 2015 |
| Rogan Bricklaying Ltd | Construction | 2023 |
| Rowallane Community Hub | Agriculture & fishing | 2011 |
| Rowe Construction Ltd | Extraterritorial | 1999 |
| S.Jola Ltd | Hospitality | 2024 |
| S.P.B. Contracts Ltd | Construction | 2008 |
| Safe & Sound Daycare Nurseries Ltd | Health & social care | 2021 |
| Safe Systems Engineering Limited | Professional & scientific | 2015 |
| Saintfield Accountancy Services Limited | Professional & scientific | 2012 |
| Saintfield Mill Holding Company Ltd | Households | 2025 |
| Saintfield Self Storage Ltd | Administrative & support | 2023 |
| Saintfield Show Limited | Arts & recreation | 2006 |
| SAM Mclernon Holdings Limited | Professional & scientific | 2005 |
| Samuel Robinson & Sons (Cluntagh), Limited | Agriculture & fishing | 1964 |
| SB Plastering Services Ltd | Construction | 2016 |
| Sbentertainments Ltd | Information & communication | 2025 |
| Seaforde Working Vintage Club Limited | Other services | 2004 |
| Seeconnell Initiative | Other services | 1990 |
| Selfbuild Ireland Limited | Information & communication | 1995 |
| SEN HR Services Ltd | Health & social care | 2021 |
| Seymour Commercial Ltd | Administrative & support | 2019 |
| SFE Holdings Limited | Financial services | 2026 |
| Ship Shape Property (IRE) Ltd | Real estate | 2021 |
| Show Grooms International Ltd | Administrative & support | 2017 |
| Silver Tongue Translations Limited | Other services | 2013 |
| Sonamove Limited | Health & social care | 2021 |
| Spa Wind Turbines Limited | Energy | 2014 |
| Spa Woods Ltd | Education | 2024 |
| Sproule House Management Company Limited | Households | 2018 |
| SRS Dental Laboratory Ltd | Health & social care | 2010 |
| SS Capital Advisory Limited | Financial services | 2023 |
| SS Capital Holdings Limited | Financial services | 2025 |
| SS Capital Racing Limited | Arts & recreation | 2025 |
| Stang Limited | Information & communication | 2001 |
| Station Logistics Freight Forwarder Ltd | Transport & logistics | 2025 |
| Sterling Farming Ltd | Agriculture & fishing | 2024 |
| Stil Properties Ltd | Real estate | 2023 |
| Structure DSR Ltd | Construction | 2025 |
| Studio Symphony Orchestra - the | Arts & recreation | 2003 |
| Successful Marketing Ltd | Information & communication | 2023 |
| Sunpower Energy Ltd | Construction | 2025 |
| Supreme Laundry Ltd | Other services | 2018 |
| Talent Route AI Ltd | Information & communication | 2024 |
| Tannaghmore Estates Ltd | Hospitality | 2021 |
| Tempus Project Management Limited | Professional & scientific | 2014 |
| Tenedos Property Limited | Real estate | 2018 |
| THE Bridge Chip Shop Ltd | Hospitality | 2024 |
| THE Friendly Gym Ltd | Arts & recreation | 2025 |
| THE Kingdom of Tableware Limited | Wholesale & retail | 2024 |
| THE Splash LAB Studio Ltd | Arts & recreation | 2025 |
| THE Sunbed & Beauty Salon Limited | Other services | 2019 |
| THE Website PAL Ltd | Information & communication | 2023 |
| THE Workshop Ballynahinch CIC | Health & social care | 2024 |
| Thornhill Contracts Limited | Construction | 2018 |
| Tikka Town (N.I) Limited | Hospitality | 2020 |
| Timpany Construction Limited | Construction | 2005 |
| Tippettpr Limited | Professional & scientific | 2011 |
| TJ Shields & SON Ltd | Extraterritorial | 2013 |
| TM Construction & Developments Limited | Construction | 2016 |
| Todds Hill Park Management Company Limited | Households | 2005 |
| Transcription & Stenography Services NI Ltd | Administrative & support | 2014 |
| Travel Smart Worldwide Limited | Administrative & support | 2016 |
| Trident Engineering Services (NI) Ltd | Extraterritorial | 2011 |
| Trident Engineering Solutions Limited | Manufacturing | 2011 |
| Trip-Ability Limited | Construction | 2013 |
| Tullywest Care (N.I.) Ltd | Health & social care | 2017 |