---
kind: "section"
citation: "26 U.S.C. § 6521"
title: "26"
title_heading: "Internal Revenue Code"
number: "6521"
heading: "Mitigation of effect of limitation in case of related taxes under different chapters"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/26/6521"
units:
  - "Subtitle F — Procedure and Administration"
  - "Chapter 66 — Limitations"
  - "Subchapter C — Mitigation of Effect of Period of Limitations"
---

# §6521. Mitigation of effect of limitation in case of related taxes under different chapters

- (a) **Self-employment tax and tax on wages—** In the case of the tax imposed by [chapter 2](/usc/26/chstA/ch2.md) (relating to tax on self-employment income) and the tax imposed by [section 3101](/usc/26/3101.md) (relating to tax on [employees](/usc/26/7701.md?p=a-20) under the Federal Insurance Contributions Act)—
  - (1) If an amount is erroneously treated as self-employment income, or if an amount is erroneously treated as [wages](/usc/26/7701.md?p=j-3), and
  - (2) If the correction of the error would require an assessment of one such tax and the refund or credit of the other tax, and
  - (3) If at any time the correction of the error is authorized as to one such tax but is prevented as to the other tax by any law or rule of law (other than [section 7122](/usc/26/7122.md), relating to compromises),

  then, if the correction authorized is made, the amount of the assessment, or the amount of the credit or refund, as the case may be, authorized as to the one tax shall be reduced by the amount of the credit or refund, or the amount of the assessment, as the case may be, which would be required with respect to such other tax for the correction of the error if such credit or refund, or such assessment, of such other tax were not prevented by any law or rule of law (other than [section 7122](/usc/26/7122.md), relating to compromises).

- (b) **Definitions—** For purposes of [subsection (a)](#a), the terms “self-employment income” and “[wages](/usc/26/7701.md?p=j-3)” shall have the same meaning as when used in [section 1402(b)](/usc/26/1402.md?p=b).

## Source credit

(Aug. 16, 1954, ch. 736, 68A Stat. 814.)

## Notes

### Editorial Notes

### References in Text

The Federal Insurance Contributions Act, referred to in subsec. (a), is act Aug. 16, 1954, ch. 736, §§ 3101, 3102, 3111, 3112, 3121 to 3128, 68A Stat. 415, which is classified generally to chapter 21 (§ 3101 et seq.) of this title. For complete classification of this Act to the Code, see section 3128 of this title and Tables.