Section 2 of the IRS Data Book deals with IRS examinations (audits) of returns to determine if income, expenses, and credits are being reported accurately. The IRS enforces tax law in a number of ways; the more common methods include correspondence (examination by mail) and field (face-to-face audit) examinations. This section provides information about examinations of most types of tax returns such as income tax, estate and gift tax, employment tax, and excise tax. Information is also provided about examinations of tax-exempt organizations.

Two charts showing the total number of returns examined and the method in which the returns were examined in fiscal year 2018. A majority of the returns examined were through correspondence examination

View chart details (XLS). For additional graphs from this section, download the PDF of this year’s Data Book.

Highlights of the Data

  • The IRS audited almost 1.0 million tax returns, approximately 0.5 percent of all returns filed in Calendar Year 2017 (Table 9a).
  • IRS conducted the majority of Fiscal Year 2018 audits, 74.8 percent, via correspondence. The remaining 25.2 percent were conducted in the field (Table 9a).

  • Of the almost 1.0 million examinations of tax returns, almost 30,000 resulted in additional refunds to the taxpayer totaling more than $6.0 billion (Table 12).

Index of Data Book Tables


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