IRS says they sent my refund to my bank 4 days ago. My bank hasn't received the refund. How do I find where my refund is?

[mesquitebean]

Is the refund supposed to go directly from the IRS to your bank account?   If so, it may arrive today.   You can phone the bank and ask them if they can see any information yet if they are getting an ACH deposit from the IRS/Treasury, or if they refused one and sent it back.  Ask for the department familiar with ACH.

If you chose any option that use a third-party bank, then the funds travel a different route.   Did you happen to pay any fees out of your refund, or choose the "up to 5 days early" offer, or have a Refund Advance?  In those situations, the funds go first from the IRS to the third-party bank, and then that third-party bank sends the rest to your bank (or card) in a second direct deposit.

[CatinaT1]

Your refund could be offset. The IRS and State Governments have the ability to offset a refund to pay for certain past due debts.  You generally will receive a letter stating what the offset was for.   

The IRS provides a toll-free number, (800) 304-3107, to call for information about tax offsets.