To revoke or cancel an EFW payment, contact the IRS e-file Payment Services at 1-888-353-4537. Cancellation requests must be received no later than 11:59 p.m. ET two business days prior to the scheduled payment date. If there is a change to the bank account information provided on the return or form, call this number to cancel the scheduled payment. Note that once your extension is accepted, the information pertaining to your payment (such as account information, payment date, or amount) cannot be changed. If changes are needed, your only option is to cancel the payment and choose another payment method. If a payment is returned by your financial institution (e.g., due to insufficient funds, incorrect account information, closed account, etc.) the IRS will mail a Letter 4870 to the address they have on file for you, explaining why the payment could not be processed and providing alternate payment options. If your financial institution is unable to process your payment request, you will be responsible for making other payment arrangements – you will also be responsible for any penalties and interest incurred. Make sure to contact your financial institution immediately if there is an error in the amount withdrawn.