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The subscription billing renewal date

A subscription’s billing period depends on two factors:
  • The recurring interval of its subscription, such as monthly, yearly, weekly, and so on.
  • The billing cycle anchor is the reference point that aligns future billing period dates. It sets the day of week for week intervals, the day of month for month and year intervals and the month of year for year intervals. The default value is either the subscription creation date or the trial end date (if you’re using a trial period). You can also explicitly set this value at the time you create the subscription.
Billing cycle anchors are UNIX timestamps in seconds from the current epoch.
The following are examples of monthly subscriptions with different billing periods:
  • A monthly subscription with a billing cycle anchor date of September 2 always bills on the second day of the month.
  • A monthly subscription with a billing cycle anchor date of 31 January bills the last day of the month closest to the anchor date, so 28 February (or 29 February in a leap year), then 31 March, 30 April, and so on.
  • A weekly subscription with a billing cycle anchor date of Friday, 3 June bills every Friday thereafter.
Full billing periods start on the first full invoice (Invoices are statements of amounts owed by a customer. They track the status of payments from draft through paid or otherwise finalized. Subscriptions automatically generate invoices, or you can manually create a one-off invoice) date, which is often the same as the billing cycle anchor and is always interval-aligned with it.