In the United States, paper checks are the most widely used mechanism aside from cash to purchase goods and services. The use, production, and collection of paper checks is a costly process involving substantial societal resources. The most recent estimates of the total resources used in check processing were put forth in a 1987 paper by David B. Humphrey and Allen Berger. This paper updates the calculation of the total social cost of paper checks and their electronic substitute, automated clearinghouse payments.