- Open University of Catalonia DEQARINST0846 ES0076 Universitat Oberta de Catalunya Barcelona (Spain)
- EADA School of Upper Management and Business Administration (Open University of Catalonia) DEQARINST8817 EADA, Escola d'Alta Direcció i Administració Barcelona (Spain)
- Open University of Catalonia, Open University of Catalonia DEQARINST5054 Universitat Oberta de Catalunya Barcelona (Spain)
- Open University of Cyprus DEQARINST0223 CY0002 Ανοικτό Πανεπιστήμιο Κύπρου Latsia (Cyprus)
- Open University of Madrid (UDIMA) DEQARINST0819 ES0049 Universidad a Distancia de Madrid (UDIMA) Madrid (Spain)
- Open University of Madrid (UDIMA), Faculty of Economics and Business Sciences DEQARINST5453 Facultad de Ciencias Económicas y Empresariales Spain
- Open University of Madrid (UDIMA), Faculty of Education and Health Sciences DEQARINST5348 Facultad de Ciencias de la Salud y de la Educación Spain
- Open University of Madrid (UDIMA), Faculty of Legal Sciences DEQARINST5347 Facultad Ciencias Jurídicas Spain
- Open University of Madrid (UDIMA), Faculty of Social Sciences and Humanities DEQARINST5454 Facultad de Ciencias Sociales y Humanidades Spain
- Open University of Madrid (UDIMA), Faculty of Technical Sciences and Engineering DEQARINST5455 Facultad de Ciencias Técnicas e Ingeniería Spain
- Open University of Portugal DEQARINST2114 PT0015 Universidade Aberta Lisboa (Portugal)
- Open University of the Netherlands DEQARINST1727 NL0014 Open Universiteit Heerlen (Netherlands)
- Opole University of Technology DEQARINST1929 PL0140 Politechnika Opolska Opole (Poland)
- Osh State University DEQARINST5930 Ош мамлекеттик университети Osh (Kyrgyzstan)
- Osh Technological University DEQARINST5929 Ош технологиялык университети Osh (Kyrgyzstan)
- Oslo Metropolitan University DEQARINST1815 NO0069 Oslomet – storbyuniversitetet Oslo (Norway)
- Oslo National Academy of the Arts DEQARINST1805 NO0042 Kunsthøgskolen i Oslo Oslo (Norway)
- Oslo New University College DEQARINST7622 NO0076 Oslo Nye Høyskole Oslo (Norway)
- Osnabrück University DEQARINST0380 DE0067 Universität Osnabrück Osnabrück (Germany)
- Osnabrück University of Applied Sciences DEQARINST0584 DE0302 Hochschule Osnabrück (FH) Osnabrück (Germany)