Gender and altruism in a random sample

•When all treatment arms are aggregated, no significant gender differences are found.•Controlling for gender of the counterpart does not affect the results.•When priming there is suggestive evidence of gender differences in altruism.•Post-hoc analysis suggests that the priming effect only occurs in mixed-gender contexts.•More studies on gender differences in altruism in representative samples are needed. We study gender differences in altruism in a large random sample of the Swedish population using a standard dictator game. Beside a baseline treatment we implement a priming treatment where participants are reminded of their gender, and two treatments with known male and female counterpart respectively. We find suggestive evidence that women are more altruistic than men only in the priming treatment. A post-hoc analysis using data on interviewer gender to explore gender context effects indicates that priming affects behavior only in mixed-gender contexts.