If you do not use the full amount of a cash advance for a trip, the procedure for dealing with the unused amount depends on whether the reconciliation was automatic or manual (see Reconciling a Cash Advance Request with an Expense Report).
In the case of automatic reconciliation, the unused amount is displayed on the Cash Advances tab and can be used for future expenses.
If reconciliation was done manually, you need to give back the remaining amount.
Having reconciled the cash advance with the expense report, you click the Notify a cash advance return icon on the cash advance line in the expense report.
Doing so displays a form where you fill in the details of the amount you are returning.
Enter the date of the return, and choose one of these return methods:
Enter the amount you are returning, ensure that the correct currency is shown, and click Notify.
The amount shown in the cash advance item of the expense report is reduced by the amount returned.
Click show details on the cash advance item to see details of the returned amount: