### Question
What is the definition of testing period?


### Answer
The definition of **testing period** is as follows in *26 U.S.C. § 223*:

> the period beginning with the last month of the taxable year referred to in subparagraph (A) and ending on the last day of the 12th month following such month

#### Citation:
  - *26 U.S.C. § 223*
  - Heading: **Subtitle A-Income Taxes > CHAPTER 1-NORMAL TAXES AND SURTAXES > Subchapter B-Computation of Taxable Income > PART VII-ADDITIONAL ITEMIZED DEDUCTIONS FOR INDIVIDUALS**

