Open a job and click on the Billings tab:
The Work Retainage and Materials Stored Retainage percentages cannot be changed directly after a sales order or invoice is entered but must be changed by clicking on either the Change Work Retainage or the Change Materials Retainage button.
Enter the new Work Retainage Percent rate and set the Process Date. This process will adjust the retainage and create general ledger transactions on all sales invoices that include retainage. The invoice accounts receivable G/L account will be debited the amount of the retainage reduction and the job's customer retainage account will be credited the same amount. If an invoice was paid in full and the retainage percentage was reduced, the invoice could include a balance due once again.
The Materials Stored Retainage is zeroed for all past invoices when a new invoice is processed; materials stored retainage will only be present on the most recent invoice. This retainage is zeroed at the time the job is closed or by using the Change Materials Retainage button.