Topic No. 206 Dishonored Payments | Internal Revenue Service (irs.gov)
On my IRS e-file, I entered an incorrect ACH routing number, and the return was accepted. I made the same mistake with my state taxes, but that was resolved.
The IRS payment still showed up on irs.gov/account, so I called the IRS Payment Services at [phone number removed], but they weren’t able to help. I logged into irs.gov/account and submitted a new payment for TY2021, and saw the withdrawal the next day.
Topic 206 says there can be a 2% penalty for a dishonored check over $1,250. Of course, my bank did not dishonor the payment because they never received it due to the wrong routing number.
with a bad routing number, the transfer will go back to the IRS to issue a paper check. I've never heard or seen them charge a fee for this. it could take many weeks before you get the check in the mail.
a dishonored check is when you send the IRS payment and the check bounces for whatever reason.
Re: "... back to the IRS to issue a paper check ..."
I am the one paying the IRS for a balance due. The first payment to them failed, the second succeeded.