The impact of timing and type of donation decision on charitable giving

We study how the timing and the type of donation decisions affect charitable giving. In an online real-effort experiment with a subsistence income constraint, participants could donate to a charity either before or after they worked to generate income. We find no evidence that timing affects the propensity to donate or the amounts donated. However, if a donation is expressed as a share of future income rather than an absolute amount, more people donate and they donate larger amounts. Advance commitment does not appear to have a motivational effect on effort. Our findings suggest that requesting donations as a share of future income may enhance charitable giving.