A dormant account is an account where you have not completed a transaction yourself (i.e. deposit or withdrawal) during the last 12 months. Completing a branch withdrawal, transferring funds from the account, completing an ATM withdrawal or completing an EFTPOS transaction will reactivate the account.
If the dormant account is an everyday options sub-account, to reactivate, transfer funds into the sub-account and then transfer funds out of the account again. This process will re-activate the account.