What if an ITIN holder submits a renewal and then files a tax return before receiving confirmation that their ITIN has been renewed?

If a taxpayer files a return with an expired ITIN, the return will be processed.  However, certain tax credits and/or any claimed exemptions will be disallowed, and no refund will be paid at that time.  IRS will send the taxpayer a notice with the appropriate adjustments that may result in a balance due and penalties. The notice will also inform the taxpayer that the ITIN has expired, and they will have to renew. This process will delay the return and any refund associated with the expired ITIN(s).