CFR › Title 26 › Part 301 › §301.6654-126 CFR §301.6654-1Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy linkFor regulations under section 6654, see §§ 1.6654-1 to 1.6654-5, inclusive, of this chapter (Income Tax Regulations).