# Treas. Reg. § 1.66-5: Effective date.

Source: eCFR as of 2026-10-19 <https://www.ecfr.gov/current/title-26/section-1.66-5>. Interprets 26 U.S.C. § 66.

Sections 1.66-1 through 1.66-4 are applicable on July 10, 2003. In addition, § 1.66-4 applies to any request for relief filed prior to July 10, 2003, for which the Internal Revenue Service has not issued a preliminary determination as of July 10, 2003. 

[T.D. 9074, 68 FR 41070, July 10, 2003]