How do I change my bank information for the stimulus ?

[NCperson]

unfortunately, you can't to prevent fraud...... this is the IRS FAQ on the topic 

Q D4. What if the bank account number I used on my recent tax return is closed or no longer active? ...

A4. If the account is closed or no longer active, the bank will return the deposit and you will be issued a check that will be mailed to the address we have on file for you. This is generally the address on your most recent tax return or as updated through the United States Postal Service (USPS).

As required by law and for security reasons, a letter about the Payment will be mailed to each recipient’s last known address within 15 days after the Payment is made. The letter will provide information about the Payment.

[xmasbaby0]

Your banking information cannot be changed after your tax return has been filed and accepted.

Banking information does not go from TT to the IRS until you file your 2020 tax return and it is accepted. The IRS will begin to accept  and process 2020 returns at the end of January 2021.

You enter/change banking information in the FILE section before you file your 2020 return. Changing it on the TurboTax site does not do any good until you file your return and the IRS processes your return.   If they manage to start sending  out stimulus checks before you can change your information, we hope the IRS provides a way for you to change it with the IRS. Right now there are no new guidelines.   If your check goes to a wrong or closed account, it will be sent back to the IRS and then the IRS will mail a check to the address on your tax return.