Code of Federal Regulations Title 26, Volume 6, April 1, 2017 contains regulations governing Internal Revenue and may also be referenced as: - Code of Federal Regulations Title 26, Volume 6, April 1, 2017 - CFR Title 26 - CFR 26, Internal Revenue - CFR 26, Part 1, §§ 1.401 to 1.409, Internal Revenue This volume contains Part 1, §§ 1.401 to 1.409: - Part 1; INCOME TAXES (CONTINUED)