Staff Report, Federal Reserve Bank of New York 191
Debit cards are overtaking credit cards as the most prevalent form of electronic payment at the point of sale, yet the determinants of a ubiquitous consumer choice - debit or credit? - have received relatively little scrutiny. Several stylized facts suggest that debit-card use is driven by behavioral factors. The popular view is that debit-card use presents a puzzle for canonical economic models. However, we should not overlook standard cost-based motives for using debit cards. Principally, the 50 percent of debit-card users who revolve credit-card balances would pay interest to charge purchases on the margin and hence might rationally choose to use debit rather than credit to minimize transaction costs. Debit-card use might also be rational for consumers lacking access to a credit card or facing a binding credit limit. I document robust effects of these types of credit-card use on debit use and show that such effects are consistent with a canonical model of consumer choice. This paper also shows, however, that it is difficult to distinguish sharply between canonical and behavioral motives for debit-card use in publicly available data. More generally, I develop analytical frameworks for testing competing canonical and behavioral models and find evidence consistent with important roles for both pecuniary and psychological motives.