Recurring billing
Fixed fees billed on a schedule.
Billing > Recurring Billing bills a fixed fee on a schedule, such as a monthly accounting fee.

-
Press New Recurring Billing and choose the client, the period and how often to bill.
-
Add the services it covers, with their fees.
-
Choose whether each invoice is approved automatically, and press Approve.

The Invoices list shows every invoice the schedule will raise. Engagements set up recurring billing for you; see Engagements and their statuses.