Mark paid records an occurrence
In Bills & subscriptions, open the item and choose Mark paid or Record payment. Review the confirmation and the due occurrence being recorded.
It does not move money
This records a paid occurrence in the bill's history. It does not debit your recorded money account, create an expense transaction or send a real payment.
Keep Activity in sync
Record the real expense separately in Activity if it has not already been recorded or auto-posted. Check first so you do not create two expense records.
The next occurrence
For a repeating item, the schedule can move to its next expected date after a payment record. Refresh and review its history if the due date changed while you were working.