The bank should reject it...then several months later the IRS would send a paper check to the address on your tax return.
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Things to check anyhow;
1) Folks with investment accounts (Fidelity, Vanguard..etc) always get prompted by those providers to use their account numbers to have the refund go there...check that since perhaps you used that last year. Occasionally the refund shows up in the investment account as a result, and you didn't realize it.
2) A more major problem occurs if you happened to use yoru online account to help file a tax return for someone else last year. In that case, anything you entered for that other person would have overwritten your own data last year (and the bank info).
3) Hope you didn't have your software fees deducted from your Federal Refund...in that case, the $$ go to a third party first (different Routing/account) before they send to you....(I'm not sure what shows up for routing/acct #s in your actual filing though)
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
