A recurring billing agreement is the consent a customer gives, usually at sign-up, allowing a merchant to charge a card or bank account automatically on a set schedule, for example for a subscription, membership or instalment plan. It records the amount or how it is calculated, the frequency, the start date, how to cancel and, where there is a free trial, when paid billing begins. Card network rules require merchants to obtain and keep this consent and to flag later charges as merchant-initiated transactions, which in Europe can be exempt from strong customer authentication after the first payment. The equivalent for bank account debits is a direct debit mandate. Unclear agreements are a frequent cause of disputes, and regulators in several countries have targeted subscription practices that make cancellation hard. Also see recurring payments and chargebacks.