- SM Systems and Research Corporation
- SRI International [Menlo Park]
- SRON Netherlands Institute for Space Research
- STFC Rutherford Appleton Laboratory
- STRATO - LATMOS
- SUPA School of Physics and Astronomy [University of St Andrews]
- SUPELEC-Campus Gif
- Saint Petersburg State Polytechnical University
- San Diego State University
- San Jose State University [San Jose]
- Santa Fe Energy Research Corp.
- School of Chemistry [Leeds]
- School of Chemistry [Wollongong]
- School of Chemistry and Physics [Durban]
- School of Earth and Atmospheric Sciences [Atlanta]
- School of Earth and Environment [Leeds]
- School of Earth and Environmental Sciences [Pullman]
- School of Earth and Environmental Sciences [Seoul]
- School of Earth, Atmospheric and Environmental Sciences [Manchester]
- School of Environmental Sciences [Durban]
- School of Environmental Sciences [Norwich]
- School of Geosciences [Edinburgh]
- School of Physical Sciences [Irvine]
- School of Physics [Sydney]
- School of Physics and Astronomy [Exeter]
- School of Physics. Trinity College of Dublin
- Science Applications International Corporation
- Science Applications International Corporation (SAIC)
- Science Systems and Applications, Inc. [Hampton]
- Science Systems and Applications, Inc. [Lanham]
- Science and Application International Corporation
- Science and Art Innovation Inc.
- Science and Technology Branch
- Science and Technology Facilities Council
- Sciences Pour l’Environnement
- Scientific Production Enterprise Astron Electronics
- Scientific-Industrial Enterprise AFAR
- Scottish Universities Physics Alliance
- Scripps Institution of Oceanography
- Sensors and Software
- Seoul National University [Seoul]
- Serco S.p.A. [Frascati]
- Service Central d'Analyse
- Service d'aéronomie
- Service de Chimie Quantique et Photophysique
- Service hydrographique et océanographique de la Marine
- Services communs OMP
- Servicio Meteorológico Nacional [Buenos Aires]
- Siberian Branch of the Russian Academy of Sciences
- Sid Richardson College
- Smithsonian Institution
- Société ALBEDO Technologies
- Société Cimel Électronique
- Société Européenne de Systèmes Optiques
- Société Quantel [Les Ulis]
- Sodankylä Geophysical Observatory
- Solar-Terrestrial Environment Laboratory [Nagoya]
- Sonnenborgh Observatory
- Sorbonne Université
- South African Government
- South African National Space Agency
- South African Weather Service
- Southwest Research Institute [Boulder]
- Southwest Research Institute [San Antonio]
- Space Astronomy Laboratory
- Space Dynamics Laboratory [Logan]
- Space Environment Technologies [Pacific Palisades]
- Space Physics Research Laboratory [Ann Arbor]
- Space Research Centre [Leicester]
- Space Research Centre of Polish Academy of Sciences
- Space Research Institute of Austrian Academy of Sciences
- Space Research Institute of the Russian Academy of Sciences
- Space Science Division [San Antonio]
- Space Science Institute [Boulder]
- Space Science and Astrobiology Division at Ames
- Space Science and Engineering Center [Madison]
- Space Science and Engineering Division [San Antonio]
- Space Science and Technology Department [Didcot]
- Space Sciences Laboratory [Berkeley]
- Space Systems Finland Ltd
- Space Systems Research Corporation
- Space Telescope Science Institute
- Space and Atmospheric Physics Group [London]
- Spanish Space Agency
- Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique
- St Petersburg State University
- Stanford University
- State University of New York
- Station de bioclimatologie
- Sterrewacht Leiden
- Stevens Institute of Technology [Hoboken]
- Stinger Ghaffarian Technologies, Inc.
- Stockholm University
- Stony Brook University [SUNY]
- Stratégies Mer et Littoral SAS
- SwRI Planetary Science Directorate [Boulder]
- Swedish Defense Research Agency
- Swedish Institute of Space Physics [Kiruna]
- Swedish Institute of Space Physics [Uppsala | Kiruna]
- Swedish Meteorological and Hydrological Institute
- Swedish Space Corporation
- Swiss Federal Office of Metrology
- Sydney Institute for Astronomy
- Synthèse et réactivité des substances naturelles [UMR 6514]
- Systèmes de Référence Temps Espace