Free IRS notice check
Interpret your notice and see your deadline — free, no account required. This tool covers the notice types it has verified data for and validates your selection against that list; it will refuse anything else rather than guess.
Not tax advice. CP523 Rescue is a self-help document tool — not a law firm, not a tax professional, and not affiliated with the IRS. Nothing here is tax or legal advice, and no particular outcome is guaranteed. Verify policy details against your IRS notice and irs.gov.