- Takuvik Joint International Laboratory ULAVAL-CNRS
- Tampere University of Technology [Tampere]
- Tartu Observatory
- Technical University Eindhoven
- Technical University of Berlin | Technische Universität Berlin
- Technique
- Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig]
- Technische Universität Darmstadt - Technical University of Darmstadt
- Technische Universität Dresden = Dresden University of Technology
- Technische Universität Graz
- Technische Universität Munchen - Technical University Munich - Université Technique de Munich
- TechSource Inc.
- Tecnológico de Monterrey = Monterrey Institute of Technology
- Tel Aviv University
- Télécom Bretagne
- Télécom Paris
- Télécom ParisTech
- Télescope héliographique pour l'étude du magnétisme et des instabilites solaires
- Telespazio
- Telespazio France
- Telespazio Germany GmbH
- Tennessee State University
- Terres Australes et Antarctiques Françaises
- Territoires, Environnement, Télédétection et Information Spatiale
- Texas A&M University [College Station]
- Texas A&M University [Galveston]
- Texas State University
- Thales Air Systems
- Thales Alenia Space Italia
- Thales Alenia Space [Toulouse]
- Thales Avionics
- Thales Avionics Electrical Motors
- THALES [France]
- Thales Research and Technology [Palaiseau]
- Thayer School of Engineering
- The Aerospace Corporation
- The Arctic University of Norway [Tromsø, Norway]
- The Belgian User Support and Operations Centre
- The Boeing Company
- The Bradley Department of Electrical and Computer Engineering [Blacksburg]
- The Central Astronomical Observatory of the Russian Academy of Sciences [Pulkovo]
- The George Washington University
- The Hebrew University of Jerusalem
- The Hong Kong Polytechnic University [Hong Kong]
- The Jacob Blaustein Institutes for Desert Research
- The James Hutton Institute
- The Natural History Museum [London]
- The Netherlands Organisation for Applied Scientific Research
- The Ohio State University [Columbus]
- The Open University [Milton Keynes]
- Théorie et métrologie
- Thermo Fisher Scientific (Bremen) GmbH
- Thermo Fisher Scientific Inc.
- the Russian Academy of Sciences [Moscow, Russia]
- The Shanghai Center for Urban Environmental Meteorology
- The Swedish Mapping, Cadastral and Land Registration Authority
- The University Centre in Svalbard
- The University of Electro-Communications [Tokyo]
- The University of Hong Kong
- The University of New Mexico [Albuquerque]
- The University of Sydney
- The University of Tennessee [Knoxville]
- The University of Texas at San Antonio
- The University of the West Indies
- The University of Tokyo
- Thirty Meter Telescope Observatory
- Thons tropicaux et écosystèmes pélagiques : taxies, interactions et stratégies d'exploitation
- Thüringer Landessternwarte Tautenburg
- Tianjin University
- TMT International Observatory
- TNO Built Environment and Geosciences
- TNO Climate, Air and Sustainability [Utrecht]
- TNO [Delf]
- TNO Institute of Environmental Sciences
- TNO Institute of Environmental Sciences, Energy Research and Process Innovation
- Tohoku Institute of Technology
- Tohoku University [Sendai]
- Tokai University
- Tokyo Gakugei University
- Tokyo Institute of Technology [Tokyo]
- Tokyo Metropolitan University [Tokyo]
- Tokyo University of Pharmacy and Life Sciences
- Tokyo University of Science [Tokyo]
- tomorrow.io
- Tongji University
- TotalEnergies
- TOTAL France S.A.
- Total Raffinage-Chimie
- TOTAL Refining and Chemical
- Total Refining Chemicals
- Tour du Valat, Research Institute for the conservation of Mediterranean Wetlands
- Towson University [Towson, MD, United States]
- Trinity College Dublin
- Trinity University
- TRIUMF [Vancouver]
- Tromsø Geophysical Observatory
- TROPO - LATMOS
- Tropospheric sounding, assimilation, and modeling group [JPL]
- Tsinghua University [Beijing]
- Tufts University [Medford]
- Tulane University
- Tuorla Observatory
- Tyvak Nano-Satellite Systems Inc.