| Stowood Limited | Professional & scientific | 2014 |
| Stowood Scientific Instruments Ltd | Manufacturing | 2004 |
| Straight-Thru Ltd | Professional & scientific | 2024 |
| Strata Accountants Limited | Professional & scientific | 2015 |
| Strata Capital Group Limited | Information & communication | 2026 |
| Strategically Blonde Consulting Limited | Professional & scientific | 2012 |
| Strategox Limited | Professional & scientific | 2020 |
| Stratford Apartments Ltd | Real estate | 2007 |
| Strathaven Corporate Finance Limited | Financial services | 2021 |
| Stratton Audley Manor House (Management) Limited | Households | 1974 |
| Strauss Interiors Limited | Professional & scientific | 2014 |
| Streamlines Aero Ltd | Professional & scientific | 2021 |
| Streams of Joy Oxford Limited | Other services | 2025 |
| Strengths Focused Leadership Ltd | Professional & scientific | 2014 |
| Stride Estate Planning Limited | Financial services | 2013 |
| Strideor Ltd | Wholesale & retail | 2026 |
| String Media Ltd | Information & communication | 2014 |
| Strong Energy Development (UK) Ltd | Wholesale & retail | 2023 |
| Stryker Design Limited | Administrative & support | 2017 |
| Stryve Services Ltd | Information & communication | 2025 |
| STS Pharma Limited | Health & social care | 2010 |
| Stuart Larkin and Associates Limited | Professional & scientific | 2002 |
| Stuart Mabbutt Gardening Ltd | Administrative & support | 2010 |
| Stuart Young Services Limited | Construction | 2019 |
| Students Education Services Limited | Hospitality | 2019 |
| Studio 11:11 Limited | Information & communication | 2009 |
| Studio Arco Ltd | Education | 2025 |
| Studio Citrine Ltd | Wholesale & retail | 2026 |
| Studio Koni Limited | Wholesale & retail | 2018 |
| Studio LI Ltd | Information & communication | 2024 |
| Studio LIO Ltd | Professional & scientific | 2025 |
| Studio Picture Cards Ltd. | Arts & recreation | 2017 |
| Studio PT Oxford Limited | Arts & recreation | 2024 |
| Study in Oxford Ltd | Education | 2024 |
| Stuk Services Limited | Construction | 2017 |
| Stunbeam Ltd | Administrative & support | 2025 |
| Stunning Show Ltd | Administrative & support | 2024 |
| Styring Limited | Arts & recreation | 2012 |
| Suave Surgical Limited | Wholesale & retail | 2026 |
| Sub-Saharan Children's Hope Trust | Education | 2011 |
| Suba TM Ltd | Administrative & support | 2021 |
| Subcooled Airconditioning Limited | Construction | 2006 |
| Subkult Ltd | Wholesale & retail | 2025 |
| Subphonic Limited | Information & communication | 2026 |
| Successful Failures Ltd | Administrative & support | 2025 |
| Sudanese Community Oxford Shir UK Ltd | Other services | 2025 |
| SUE Hitchcox Ltd | Real estate | 2014 |
| SUE Pavord Medical Services Ltd | Professional & scientific | 2016 |
| SUH Distribution Ltd | Wholesale & retail | 2026 |
| Suite Nights Ltd | Hospitality | 2023 |
| Suited Tutor Ltd | Education | 2019 |
| Sulos Ltd | Wholesale & retail | 2023 |
| Sumanleela Limited | Real estate | 2020 |
| Sumiya Group Limited | Manufacturing | 2025 |
| Summer Discovery UK Ltd | Other services | 2024 |
| Summer Fields School Trust,Limited | Education | 1955 |
| Summer Institute of Linguistics Limited | Extraterritorial | 1964 |
| Summer Snow Properties Ltd | Real estate | 2019 |
| Summertown Arts Projects Limited | Arts & recreation | 2024 |
| Summertown Barbers Ltd | Other services | 2023 |
| Summertown Bespoke Ltd | Other services | 2025 |
| Summertown Clinic Limited | Health & social care | 2021 |
| Summertown Clinic Oxford | Health & social care | 2003 |
| Summertown Court Limited | Households | 1993 |
| Summertown Cycles Ltd | Wholesale & retail | 2021 |
| Summertown Executive Ltd | Transport & logistics | 2017 |
| Summertown Films Ltd | Information & communication | 2022 |
| Summertown Limited | Real estate | 2016 |
| Summertown Software Ltd | Other services | 2016 |
| Summertown Stars AFC | Arts & recreation | 2020 |
| Summertown Tailoring Ltd | Other services | 2021 |
| Summertown Valeting Co. Limited | Administrative & support | 2026 |
| Summerworth Oxford Limited | Real estate | 1960 |
| Summit Brands Limited | Administrative & support | 2019 |
| Summit Publications Ltd | Information & communication | 2020 |
| Sumy Logistics Ltd | Transport & logistics | 2024 |
| Sun Mirrors Ltd | Wholesale & retail | 2025 |
| Sunbeam Talbot Darracq Register Limited | Other services | 2002 |
| Sundawn Studios Limited | Information & communication | 2025 |
| Sunderland Court Maintenance Company Limited | Households | 1986 |
| Sundra Investments Limited | Real estate | 1959 |
| Sunflower Properties (Oxfordshire) Limited | Real estate | 2020 |
| Sunflowers Supportive Care Limited | Health & social care | 2024 |
| Sunlightmoon Ltd | Wholesale & retail | 2021 |
| Sunni Builders Ltd | Construction | 2019 |
| Sunningwell Management Limited | Households | 1988 |
| Sunny International Limited | Education | 1996 |
| Sunnymead Consulting Ltd | Information & communication | 2011 |
| Sunrise Meat & Poultry Limited | Wholesale & retail | 2016 |
| Sunrise Reporting Limited | Professional & scientific | 2014 |
| Sunshine Corporation Limited | Real estate | 2018 |
| Sunshine Oxon Cleaning Services Ltd | Administrative & support | 2021 |
| Sunshine Pearl Ltd | Health & social care | 2015 |
| Sunshine REG Services Ltd | Public administration | 2023 |
| Sunshine Support Ltd | Education | 2024 |
| Sunwoo Oxford Ltd. | Wholesale & retail | 2021 |
| Sunwords Holdings Limited | Wholesale & retail | 2026 |
| Sunzg Limited | Hospitality | 2014 |
| Super Being Labs Ltd | Professional & scientific | 2013 |
| Super Benji Limited | Information & communication | 2023 |