An IRS audit notice lands in your mailbox and your stomach drops. It’s one of the most stressful pieces of mail a taxpayer can receive — and most people have no idea what comes next.
Here’s the truth: the process is more structured and more manageable than it feels in that moment. Understanding exactly what happens at each stage removes the fear of the unknown and helps you respond effectively.
First: What Kind of Audit Is This?
Not all IRS audits are the same. The notice you receive will indicate which type you’re dealing with:
Correspondence Audit (most common): Conducted entirely by mail. The IRS sends a letter asking you to verify a specific item — often a deduction, an income figure, or a dependent claim. You respond with documentation. These are typically the simplest to resolve.
Office Audit: You’re asked to bring documents to a local IRS office and meet with an auditor in person. More involved than correspondence audits, but still focused on specific issues.
Field Audit: An IRS agent comes to you — your home, your business, or your accountant’s office. These are the most comprehensive and typically reserved for businesses or complex returns.
Automated Underreporter (CP2000) Notice: This isn’t technically an audit, but it’s treated like one. The IRS identified a discrepancy between what you reported and what was reported by a third party (your employer, a client, a bank). You have 60 days to agree, dispute, or provide additional information.
The Audit Timeline: Stage by Stage
Stage 1: The Notice Arrives (Day 0)
IRS audit notices almost always come by mail — specifically, certified mail with a return receipt. The notice will include:
- The tax year(s) under review
- The specific issues being examined
- What documents or information the IRS wants
- A deadline for your response (typically 30-60 days)
What to do immediately: Read the notice carefully. Note the deadline. Don’t ignore it — failing to respond by the deadline allows the IRS to make a determination without your input, which is almost never in your favor.
Stage 2: Gather Your Documentation (Days 1–14)
Before you respond to anything, gather every document related to the items under review:
- Bank statements for the relevant period
- Receipts, invoices, and records for any deductions questioned
- Prior year returns for context
- Any correspondence with the IRS about this tax year
- Your original return and all supporting worksheets
Important: Don’t send originals. Make copies of everything. Keep originals in a safe location.
If the audit covers multiple years or complex issues, this is the point where you should seriously consider engaging a tax professional. Having representation — a CPA, tax attorney, or enrolled agent — can significantly change the outcome of an audit.
Stage 3: Submit Your Response (By the Deadline)
For a correspondence audit, your response is a letter explaining your position, accompanied by supporting documentation. Address every item the IRS raised. Don’t ignore items you can’t fully document — explain your position as clearly as possible.
For an office or field audit, your response is showing up prepared with organized records. Bring exactly what was requested — no more, no less. Volunteering additional information opens the door to additional questions.
Key principle: The burden of proof is on you. It’s your job to show that what you claimed on your return was accurate. The IRS doesn’t have to prove you wrong; you have to prove you’re right.
Stage 4: The IRS Reviews Your Response (Weeks 3–12)
After you submit your response, the IRS reviews it. For correspondence audits, this takes weeks to months. For office and field audits, the reviewer processes your documentation and may ask follow-up questions.
During this period:
- You may receive additional information requests
- An auditor may call you (or your representative) with questions
- The timeline can extend significantly if the IRS is backlogged
Stay organized and responsive. Missing a secondary deadline can result in the IRS making an adverse determination.
Stage 5: The IRS Issues Its Findings
Once the IRS has reviewed everything, they issue a report of their findings. There are three possible outcomes:
No Change: The IRS agrees with your return as filed. The audit is closed. This is the best outcome and it happens more often than people expect when documentation is solid.
Agreed: The IRS found issues and you agree with the adjustments. You’ll owe additional tax, plus interest (calculated from the original due date of the return). Accuracy-related penalties may also apply.
Disagreed: You don’t agree with the IRS’s findings. This is where the appeals process begins.
Stage 6: If You Disagree — Appeals and Next Steps
If you don’t agree with the audit findings, you have options:
IRS Appeals Office: You can request a conference with the IRS Independent Office of Appeals. This is a separate division from the auditors, and their job is to resolve disputes without litigation. Many audit disputes are settled here.
Tax Court: If Appeals doesn’t resolve the issue, you can petition the U.S. Tax Court. You don’t pay the disputed amount first — you litigate the issue and the court decides. This is typically a last resort for significant disputes.
Pay and Sue for Refund: Alternatively, you can pay the disputed amount and then sue for a refund in U.S. District Court or the U.S. Court of Federal Claims.
The appeals and litigation process can take months to years. Most disputes are resolved before reaching Tax Court.
How Long Does an Audit Take?
- Correspondence audit: 3–6 months from notice to resolution, if you respond promptly
- Office audit: 6–12 months
- Field audit: 12–24+ months for complex cases
- Appeals: Add 12–18 months if you appeal
The IRS has a 3-year statute of limitations to audit your return, measured from the later of the original due date or the date you filed. For significant underreporting (over 25% of income), that extends to 6 years. For fraud, there’s no statute of limitations.
What You Shouldn’t Do
Don’t ignore the notice. This is the most common mistake. The IRS will proceed without you.
Don’t lie or fabricate documents. This transforms a civil audit into a potential criminal matter. It’s not worth it.
Don’t respond without preparation. Rushing a response with disorganized documentation creates more problems than it solves.
Don’t represent yourself in a field audit if the stakes are high. A qualified representative knows the process, knows what to say and not say, and can advocate for you in ways you can’t advocate for yourself.
The Best Audit Is the One That Never Happens
The most effective audit strategy is a preventive one. Clean records, accurate deductions, and consistent year-over-year reporting reduce your AURA risk score and keep you out of the audit pool in the first place.
If you’ve already received a notice, take it seriously and respond promptly. If you haven’t — now is the time to build the documentation habits that protect you.
Download our free IRS Audit Risk Checklist to see where your exposure is today. Or take the free IRS Risk Score Quiz for a personalized assessment of your audit risk profile. For ongoing protection and representation if you’re ever selected, explore our AUDITPROOF service plans.