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Most IRS audits are handled by mail, take 3-6 months, and result in either no change or a modest adjustment. Only 0.4% of returns are audited, and the process is far less dramatic than people fear.
Types of IRS Audits
Audit Type
How It Works
How Common
Severity
Correspondence audit
Conducted by mail. IRS asks for specific documents
~75% of audits
Low
Office audit
You visit a local IRS office with documents
~20% of audits
Medium
Field audit
IRS agent comes to your home or business
~5% of audits
High
What Triggers an Audit
Trigger
Risk Level
Why
Unreported income (missing 1099/W-2)
π΄ Very high
IRS already has copies and compares automatically
Math errors
π΄ High
Often auto-corrected but may trigger review
Large deductions relative to income
π‘ Medium
DIF score flags statistical outliers
Home office deduction
π‘ Medium
Historically abused; invites scrutiny
Schedule C losses (year after year)
π‘ Medium
IRS may reclassify as hobby
Large charitable donations
π‘ Medium
Especially cash donations without receipts
Income over $1 million
π‘ Medium
Audit rate is 1-2% (vs. 0.4% overall)
Earned Income Tax Credit
π‘ Medium
High error rate on this credit
Amended return (Form 1040-X)
π’ Low-medium
Drawing IRS attention to your return
Random selection
π’ Low
Statistical sampling program
Audit Rate by Income Level
Income Level
Audit Rate (approx.)
Under $25,000
0.4%
$25,000-$50,000
0.2%
$50,000-$100,000
0.2%
$100,000-$200,000
0.3%
$200,000-$500,000
0.4%
$500,000-$1 million
0.6%
Over $1 million
1-2%
Over $5 million
2-4%
What Happens During a Correspondence Audit
Step
What Happens
Your Action
1
You receive IRS Letter (CP2000 or other)
Don’t panic β read carefully
2
Letter identifies specific items being questioned
Gather supporting documentation
3
You have 30 days to respond
Respond by deadline (or request extension)
4
Send copies of supporting documents
Never send originals
5
IRS reviews your response
Wait 60-90 days
6
IRS accepts, partially accepts, or rejects
Agree or appeal
Possible Outcomes
Outcome
What It Means
How Often
No change
IRS agrees your return was correct
~25% of audits
You owe more
IRS found errors; you owe additional tax + interest + penalties
~55% of audits
You owe less (refund)
IRS found you overpaid
~2% of audits
Agreed adjustment
You and IRS agree on changes
Most common resolution
Unagreed
You disagree; can appeal
You have 30 days to appeal
Your Rights During an Audit
Right
What It Means
Right to representation
You can have a CPA, tax attorney, or enrolled agent represent you
Right to know why
IRS must explain why your return was selected
Right to see evidence
IRS must show you the information they’re relying on
Right to appeal
You can appeal any IRS decision you disagree with
Right to privacy
IRS cannot discuss your audit publicly
Right to a timely resolution
IRS should complete audits as quickly as possible
Right to disagree
You can take your case to Tax Court
Penalties If You Owe More
Penalty Type
Rate
Accuracy-related penalty
20% of the underpayment
Substantial understatement (>$5K or >10%)
20% of the underpayment
Fraud penalty
75% of the underpayment
Interest
~8% annually (2026), compounding daily
Failure-to-pay (on additional balance)
0.5% per month
The Bottom Line
An audit is a document review, not a criminal investigation. Stay calm, gather your records, respond by the deadline, and hire a tax professional if the audit is complex. Most correspondence audits are resolved by simply providing documentation you should already have. If you disagree with the result, you have the right to appeal.
WealthVieu researches and writes data-driven personal finance guides using primary sources including the IRS, Bureau of Labor Statistics, Federal Reserve, and Census Bureau.
The content on Wealthvieu is for informational purposes only and should not be considered financial, tax, or investment advice. Consult a qualified professional before making financial decisions. Full disclaimer Β· Editorial policy