Title 26 › Subtitle Subtitle F— Procedure and Administration › Chapter 68— ADDITIONS TO THE TAX, ADDITIONAL AMOUNTS, AND ASSESSABLE PENALTIES › Subchapter A— Additions to the Tax and Additional Amounts › Part II— ACCURACY-RELATED AND FRAUD PENALTIES › § 6663
If any part of an underpayment on your tax return is due to fraud, a penalty of 75 percent is added on the portion caused by fraud. Once the IRS proves any part of the underpayment was fraudulent, the entire underpayment is treated as fraud unless you show, by a preponderance of the evidence, which part was not. On a joint return, a spouse is not hit with the penalty unless some part of the underpayment came from that spouse's own fraud.
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Internal Revenue Code — Source: USLM XML via OLRC
Legislative History
Reference
Citation
26 U.S.C. § 6663
Title 26 — Internal Revenue Code
Last Updated
Apr 6, 2026
Release point: 119-73