We partnered with a large online auction website to test differing messages' effects on the decision to donate to charity at checkout. Our setting, where impulsive decisions are likely to be driving donations, allows us to evaluate intuitive responses to messages prompting a donation. We find...

If social institutions, like fundraising, create incentives that generate utility from deciding to give, then some donors would decline a request to give to charity now while agreeing now to give later. This meets the classic definition of time-inconsistent choices. This is not because of a...