The global COVID‐19 outbreak has put the human race's distress tolerance abilities to the test. And, the distress experienced getting worse with each pandemic wave; however, the more flexible the person, the greater the chance of surviving. Thus, the current study aimed to examine the mediating role of personalized psychological flexibility (PPF) in the link between distress intolerance to psychological distress during the fourth wave of the pandemic in Iran. A total of 576 individuals (Mean
age
34.80, ±10.9, females 55.6%) took part in the online survey. In this national sample, PPF partially played a role in mediating the association mentioned above. Interestingly, this mediation was independent of demographic factors (age, gender, marital status, and educational level) and fear of COVID‐19, mindfulness, and satisfaction with life. So, despite the mentioned variables, accepting and using unpleasant emotions as fuel to achieve valued goals rather than avoiding them would mitigate the psychological distress during the pandemic. Consequently, public health services can aim to provide psychological flexibility enhancing interventions to decay COVID‐19‐related mental distress.