Markup and Margin Calculator (United States)

No federal law caps prices in ordinary times. The FTC's rule on unfair or deceptive fees (16 CFR Part 464), effective 12 May 2025, covers only two things: live-event tickets and short-term lodging. A seller that advertises a price for either must show the total price, meaning all mandatory fees, more prominently than any other price. Government charges and shipping may be left out of the total, but any excluded fee must be disclosed, with its nature, purpose and amount, before the buyer agrees to pay (§§ 464.1 and 464.2). Misrepresenting any fee is also banned (§ 464.3), and state laws that protect consumers more are not displaced (§ 464.4).

For all other goods, the FTC's Guides Against Deceptive Pricing apply. A "was" price is a fair comparison only if it was the real price at which the item was offered openly and regularly for a reasonably substantial period (16 CFR § 233.1).

Price-gouging limits come from the states and bite only after an emergency declaration. In Florida, section 501.160 makes it unlawful to sell an essential commodity or rent a dwelling at an unconscionable price in the declared area, for up to 60 days unless the Governor extends it. A price is presumed unconscionable if it grossly exceeds the average price in the 30 days before the declaration, unless higher costs explain it. The state attorney or the Department of Legal Affairs enforces it. Other states set different triggers, percentages and penalties.