Receiving an IRS audit letter triggers one of the most consequential 30-day windows of your financial life. The deadline is real, the stakes are substantial, and the decisions you make in the first week after receiving an audit notice will shape the entire trajectory of your case. Responding incorrectly — by sending too many documents, saying too much, or missing the deadline entirely — can expand a manageable examination into a comprehensive field audit or trigger penalties that could have been avoided. Responding correctly means understanding exactly what the IRS is asking, producing only what is required, framing your documentation strategically, and engaging professional representation before you send a single document. This guide walks through the complete response process: identifying the notice type, understanding your deadlines, gathering the right documentation, and structuring a response that closes the audit rather than invites further scrutiny. IRS audit defense Key Takeaways Your response deadline is typically 30 days from the notice date — missing it has serious consequences. Never respond to an IRS audit notice without first identifying exactly what is being questioned. Produce only what the IRS has specifically requested — over-disclosure is as dangerous as under-disclosure. All responses should be sent via certified mail with return receipt. Keep complete copies of everything. For anything beyond a simple document request, retain professional representation before responding. Step 1: Identify the Audit Notice Type and What It's Asking Before doing anything else, identify exactly what the IRS is asking. Different notices require different responses: Notice / Letter What It Means Deadline Typical Response CP2000 IRS received income info not on your return. Proposes additional tax. 60 days to agree/disagree (30 days for expedited processing) Agree, provide missing info, or dispute with documentation CP75 / CP75A EITC/CTC audit — IRS wants proof you qualify for...