We present the results of a large field study exploring consumers’ use of the Reserve “set aside”
feature on the American Express (the company) Serve prepaid card. The study aimed to address
two key questions: 1) Can certain strategies encourage consumer saving behavior; and 2) Is
saving behavior associated with better outcomes for consumers, particularly for low-income and
underserved consumers? Results from the pilot indicate that, in particular, offering customers a $10 incentive for using the savings feature during a 12-week period was highly effective at encouraging enrollment in the savings feature. Non-zero balances remained relatively constant through the remainder of the year, suggesting that for consumers still using the savings feature, balances generally did not decrease even after the treatment period ended.