This paper investigates the acceptance and usage of card payments, as well as the transactions’ demand for cash, in an economy featuring equilibrium linkages between buyers and sellers. Buyers can search for shops that accept cards, creating competition among merchants: even though card payments are costly because of fees, sellers might be willing to accept them to attract more customers. The economy features no-acceptance and full-acceptance equilibria, as well as imperfect acceptance ones that resemble the prevailing situation in most countries. After studying the existence, uniqueness, and stability properties of our equilibria, we analyze how the equilibrium card responds to changes in search frictions, consumers’ tastes, and the opportunity cost of holding cash. We bring the model to the data by solving an augmented version of the problem which features a dynamic cash management problem for buyers, and we calibrate it using data from ECB payment diaries. We use our calibrated model to compare the partial and general equilibrium implications of a policy that makes card payments cheaper for buyers, showing that when taking into account the optimal response by sellers, such policies may generate unintended consequences and lower card usage in equilibrium.