Invoicing & payments
Retainers and advance credit
The difference, and why it matters.
There are two kinds of money that arrive before an invoice does, and keeping them apart prevents double-counting.
A RETAINER secures the engagement. It is recorded on the case and never applied to an invoice. It documents a commitment, not payment for work.
AN ADVANCE is drawable credit. It sits on the case and is applied against future invoices when they are generated.
The test is simple: will this money ever be subtracted from a specific invoice? If yes, it is an advance.
BILLING A RETAINER AS REVENUE
If what you want is to invoice a client for a retainer they owe you, that is different again — log it as a flat-amount time entry so it becomes a line on an invoice they pay against. Do not also record it as a case payment, or the same money is counted twice.