What rules and which government agency regulate labeling requirements for apparel and footwear?

The U.S. Customs and Border Protection (CBP) and the Federal Trade Commission (FTC) enforce labeling laws and acts in the United States.

The Textile Fiber Products Identification Act (15 U.S.C. § 70), the Wool Products Labeling Act (15 U.S.C. § 68), the Fur Products Labeling Act  (15 U.S.C. § 69), and FTC implementing rules found at 16 C.F.R. parts 303, 300, and 301, require that most apparel products have a label with fiber content, country of origin, and manufacturer identification.

The Rule on Care Labeling of Textile Wearing Apparel and Certain Piece Goods, 16 CFR Part 423 defines the requirements for care instructions on apparel (the rule exempts shoes).