Many investment companies have begun providing their defined-contribution pension participants with individualized, retirement income projections. The U.S. Congress is currently considering whether to require them all to do so. Evidence on the potential impact is scant, though a large body of economic research suggests that individuals are not currently making optimal retirement-saving decisions. Through a field experiment, we measure how provision of retirement income projections along with enrollment information affects individuals' contributions to employer-sponsored retirement accounts. We find that the intervention boosted annual contributions to employer retirement accounts by $85, equivalent to 3.6% of the average contribution level or 0.15% of average salary, relative to those who received no intervention. In addition, randomly-assigned assumptions regarding retirement age, investment returns, and hypothetical contribution amounts were used to generate the projections and were found to have significant impacts on saving behavior. This finding suggests that care is warranted in the design and communication of projections. •Retirement-income projections affect employee contributions to savings accounts.•Effect on contributions was modest, equivalent to 0.15% of average salary.•Effect on contributions was sensitive to assumptions used to construct projections.•Care is warranted in the design and communications of income projections.