Background: Being a member of multiple social groups (multiple group membership, MGM) has beneficial effects on several health outcomes as stated by the social identity theory. MGM can also buffer the negative influences of life-altering events on well-being. The COVID-19 pandemic can be characterized as such an event. Aims: The present study investigated whether MGM is associated with better well-being for older people during the pandemic and if it has a buffer effect on the relationship between pandemic-induced fear and well-being. Method: A cross-sectional survey was conducted with a representative sample (N = 2,062) of citizens of Dresden, Germany aged 60 or older during the COVID-19 pandemic. MGM was operationalized in two different ways: as a self-assessment of the number of different social groups participants considered themselves a member of and as the number of formal groups people participated in, such as sports groups, clubs, or religious groups. Results: It was found, as expected, for both indicators that people who were members of multiple social groups reported better well-being than people with just one group membership. Participants with no group memberships had the lowest psychological well-being. MGM did, however, not buffer the negative impact of the pandemic-induced fear on well-being. Limitations: Limitations are based on our measurement methods (cross-sectional design and self-reported data). Conclusion: MGM is an important resource for older people even during a pandemic. Potential limitations of the social cure imposed by social distancing rules are discussed and related suggestions for practice are presented.