### Question
How does INTEREST define large corporate underpayment?


### Answer
Under *26 U.S.C. § 6621*, **large corporate underpayment** is defined as:

> any underpayment of a tax by a C corporation for any taxable period if the amount of such underpayment for such period exceeds $100,000

#### Citation:
  - *26 U.S.C. § 6621*
  - Heading: **Subtitle F-Procedure and Administration > CHAPTER 67-INTEREST > Subchapter C-Determination of Interest Rate; Compounding of Interest**

