Unpredictable needs are associated with lower expectations of repayment

•Mutual aid allows people to manage various sources of risks.•Some types of mutual aid create debt, while other types of mutual aid do not.•Ranchers expect repayment when needs arise predictably (vs. unpredictably).•The predictability-repayment expectation link generalizes to broader populations.•Attributions of responsibility partially mediate the predictability-repayment link. Sometimes people help one another expecting to be repaid, while at other times people help without an expectation of repayment. What might underlie this difference in expectations of repayment? We investigate this question in a nationally representative sample of US adults (N = 915), and find that people are more likely to expect repayment when needs are perceived to be more predictable. We then replicate these findings in a new sample of US adults (N = 417), and show that people have higher expectations of repayment when needs are perceived to be more predictable because people assign greater responsibility to others for experiencing such predictable needs (e.g., needing money for utilities). This is consistent with previous work based on smaller-scale societies, which shows that the predictability of needs influences expectations of repayment. Our results also add to this previous work by (1) showing that the positive relationship between predictability of needs and expectations of repayment previously found in smaller-scale communities is generalizable to the US population, and (2) showing that attributions of responsibility partially mediate this relationship. This work shows that the predictability of needs and attributions of responsibility for that need are important factors underlying the psychology of helping in times of need. [Display omitted]