If you haven’t heard anything three weeks after of filing your return, it’s time to check in with the IRS.

“After 21 days, that would be the only time you’d realize that something didn’t go through as normal,”“and you can talk to an IRS representative.”

If a month goes by and you haven’t heard anything, visit the Where’s My Refund? page for more information. If your refund has been lost, you can request a replacement check if it has been more than 28 days from when your refund was mailed.

And keep in mind if you have been waiting for a refund for longer than 45 days, there’s always the possibility that a minor error is holding things up.