| RW Motors Ltd | Wholesale & retail | 2020 |
| S Cloughley Gardening & Landscaping Ltd | Administrative & support | 2025 |
| S Fleville Contracts Ltd | Administrative & support | 2022 |
| S Glendinning Agencies Ltd | Wholesale & retail | 2021 |
| S M P Mechanical Ltd | Construction | 2019 |
| S Mcareavey & Sons Limited | Construction | 2006 |
| S&C Foster Investments Ltd | Real estate | 2024 |
| S&J Goodland Ltd | Professional & scientific | 2013 |
| S. Coleman Developments Limited | Construction | 2005 |
| S. Hull Properties Ltd | Real estate | 2023 |
| S.Carson Transport Limited | Transport & logistics | 2019 |
| S.Mul Contracting Ltd | Professional & scientific | 2019 |
| S3 Electrical Ltd | Construction | 2025 |
| SA Boom & Scissor Repairs Ltd | Manufacturing | 2020 |
| Sacha's Bistro Ltd | Hospitality | 2019 |
| Sadia Health Care Services Ltd | Health & social care | 2025 |
| Safety Compliance Support Services Limited | Other services | 2015 |
| Sahi Retail Group Ltd | Wholesale & retail | 2024 |
| Saian International Limited | Other services | 2004 |
| Saintfield Home & Garden Ltd | Wholesale & retail | 2004 |
| Sakura Nursery & Training Ltd | Health & social care | 2024 |
| Salann Limited | Professional & scientific | 2024 |
| Sally Garner Limited | | 1999 |
| Sally Mcnallys Ltd | Hospitality | 2023 |
| Salt Electrical Limited | Manufacturing | 2013 |
| Salter Coleman Limited | Professional & scientific | 2025 |
| Samify Ltd | Wholesale & retail | 2026 |
| SAN Antonio Carers Limited | Health & social care | 2023 |
| Sandymount Limited | Extraterritorial | 2004 |
| Sanitise NI Ltd | Wholesale & retail | 2021 |
| Santrix Limited | Administrative & support | 2025 |
| Saordhan Limited | Financial services | 2025 |
| Saortree Holdings Limited | Financial services | 2020 |
| Sassyspud Ltd | Wholesale & retail | 2020 |
| Saunders Nursing Care Limited | Administrative & support | 2024 |
| Savage Utilities Ltd | Construction | 2019 |
| SBE Civil Engineering Ltd | Construction | 2017 |
| SBM Contracts Limited | Construction | 2019 |
| SC Engineering (Tullylish) Ltd | Manufacturing | 2015 |
| Scaffolding UP Straight Ltd | Construction | 2021 |
| Scallywags Party & Play Centre Ltd | Arts & recreation | 2014 |
| Scarva and District Cultural Society Ltd | Other services | 2018 |
| Scarva Home Ltd | Real estate | 2024 |
| Scarvagh Consultancy Services Ltd | Information & communication | 2007 |
| School Days (Properties) Limited | Financial services | 2024 |
| School Support NI Ltd | Information & communication | 2014 |
| Scinest Ltd. | Information & communication | 2024 |
| Scottsborough Management Company Limited | Households | 2020 |
| Scratch Kitchen Ltd | Hospitality | 2025 |
| Sculptured Properties Ltd | Construction | 2025 |
| Scurmore Strategies Limited | Real estate | 2026 |
| SD Event Catering Ltd | Hospitality | 2023 |
| SDS Fabrications Ltd | Manufacturing | 2017 |
| Seafin International Limited | Transport & logistics | 2023 |
| Seagahan Estates Limited | Real estate | 2025 |
| Sean Rafferty Investments Limited | Real estate | 2022 |
| Seek and Find Jewellery Ltd | Wholesale & retail | 2018 |
| Sejb Ltd | Real estate | 2019 |
| Selah Coffee House Ltd | Hospitality | 2023 |
| Selah Storehouse Ltd | Wholesale & retail | 2024 |
| Sensory at Home Limited | Administrative & support | 2024 |
| Sergeants Portable Buildings Ltd | Manufacturing | 2025 |
| Seven Star Holidays Ltd | Administrative & support | 2025 |
| SFC Contracts Ltd | Administrative & support | 2024 |
| SGA Construction Ltd | Construction | 2008 |
| SGH Contracts Ltd | Construction | 2013 |
| Shadowtrace Ltd | Information & communication | 2025 |
| Shakable Limited | Agriculture & fishing | 2019 |
| Shalec Ltd | Hospitality | 2025 |
| Shalto Investments Ltd | Real estate | 2019 |
| Shankill (Lurgan) Community Projects | Hospitality | 1986 |
| Shankill Parish Caring Association | Health & social care | 1996 |
| Shanmourne Holdings Limited | Professional & scientific | 1985 |
| Shapeshifter Group Ltd | Financial services | 2025 |
| Shapeshifter Nutrition Ltd | Wholesale & retail | 2015 |
| Shelbourne Motors (Nissan) Limited | Wholesale & retail | 2000 |
| Shelbourne Motors Holdings Ltd | Administrative & support | 2022 |
| Sheq Point Ltd | Professional & scientific | 2011 |
| Shift Collective Ltd | Information & communication | 2026 |
| Shiny Encounter 3D Ltd | Wholesale & retail | 2023 |
| Shree Bhavan Ltd | Real estate | 2023 |
| SHS Merchants Limited | Construction | 2016 |
| Sial Diner Restaurant Limited | Hospitality | 2026 |
| Sienna Homes Ltd | Real estate | 2026 |
| Siloww Ltd | Information & communication | 2026 |
| Silver Birch (NI) Ltd | Hospitality | 2014 |
| Silver Birch Films Ltd | Information & communication | 2024 |
| Silver Cloud Care NI Ltd | Administrative & support | 2022 |
| Silver Hill Duck (UK) Ltd | Agriculture & fishing | 1989 |
| Silverline Xpress Transport Ltd | Transport & logistics | 2014 |
| Silverwood Advisory Limited | Professional & scientific | 2025 |
| Silverwood Contracts Ltd | Construction | 2025 |
| Silverwood Enterprise Limited | Manufacturing | 2004 |
| Silverwood Estate Ltd | Real estate | 1997 |
| Silverwood Facilities Management Corporation Limited | Households | 2001 |
| Silverwood Recruitment Ltd | Administrative & support | 2021 |
| Simpact Solutions CIC | Information & communication | 2025 |
| Simply Beautiful Salon Ltd | Other services | 2022 |
| Simply Puddings Limited | Manufacturing | 2017 |
| Simplyfruit (IRE) Limited | Wholesale & retail | 1999 |