There are 2 options for offsetting outstanding balances in other words writing it off:

• Give a credit to that account
• Void the transactions that are contributing to the outstanding balance

From a tax and financial perspective, option 1 of giving a credit is better. The credit will reduce your reportable revenue for the current fiscal year.

To give a credit

• Go to the Ledger or the Transactions Report
• Select a row of that account
• In Action Menu click on Add Charge or Credit
• Using the popup run the credit