Now or never! The effect of deadlines on charitable giving: Evidence from a natural field experiment

This study designs two field experiments to estimate the effect of binding deadlines and reminders on charitable giving. We sent out 62,000 e-mails and text messages to prior donors of a large Danish charity while varying the length of the deadline and whether they received a reminder. We find that a reminder increases both the likelihood of making a donation and the amount donated. We find no effect of the deadlines on the propensity to give. Instead we observe a “now-or-never” effect; either donations are made immediately or not at all. In line with the “avoiding-the-ask” theory, both shorter deadlines and the reminder increase the number of requests to be taken off the mailing list.