The method that you use depends on the way that you track and pay your sales tax:
The Agency details window displays.
QuickBooks locates all open transactions for the previous year and includes them in the current accounting period.
When you switch from cash to accrual accounting, sales tax on all unpaid sales and purchases becomes due. You must report and pay this sales tax when you file your sales tax return for the current period. See Calculate new sales tax liability.
If you have unpaid transactions that you wrote off as bad debts, adjust your sales tax return manually to remove these transactions.