What US federal law prohibits 'unfair or deceptive acts or practices' in commerce?

The US federal law that prohibits unfair or deceptive acts or practices in commerce is the Federal Trade Commission Act. Section 5(a) declares such conduct unlawful when it occurs in or affects commerce, giving the Federal Trade Commission its central consumer-protection authority.

Congress created the Federal Trade Commission in 1914, initially as an agency focused on preventing unfair methods of competition. Section 5 became especially important for consumer protection, allowing the FTC to challenge misleading advertising, deceptive omissions, fraudulent claims, and business practices that unfairly harm consumers.

The phrase is often confused with antitrust laws. The Sherman Act addresses agreements and conduct restraining trade, while the Clayton Act targets specific anticompetitive practices such as certain mergers and exclusive arrangements. The Lanham Act primarily governs trademarks and allows certain competitors to challenge false advertising. The FTC Act can overlap with these laws, but its distinctive consumer-protection wording comes from Section 5.