This paper describes the results, content, and methodology of the 2012 Diary of Consumer Payment Choice (DCPC), the first edition of a survey that measures payment behavior through the daily recording of U.S. consumers’ spending by type of payment instrument. A diary makes it possible to collect detailed information on individual payments, including dollar amount, device (if any) used to make the payment (computer, mobile phone, etc.), and payee type (business, person, government). This edition of the DCPC included about 2,500 participants and was conducted in October 2012. During that month, U.S. consumers on average made about two payments per day. For the month, they paid mostly with cash (40 percent of payments) and debit cards (24 percent), followed by credit cards (17 percent). For recurring bill payments, consumers most commonly used electronic payments and checks. Like other payment-value data, the DCPC data show correlations between the choice of payment instrument and the dollar value of expenditure. For example, consumers tend to use cash more often than other instruments for small-value payments. The results of subsequent editions of the DCPC are reported in separate papers.