Rate-of-return regulation is a system for setting the prices charged by government-regulated monopolies, such as public utilities. Its main premise is that monopolies must charge the same price that would ideally prevail in a perfectly competitive market, equal to the efficient costs of production, plus a market-determined rate of return on capital.

Rate-of-return regulation has been criticized because it encourages cost-padding and because if the rate is set too high, it encourages regulated firms to adopt capital-labor ratios that are too high. That is known as the Averch–Johnson effect, or simply "gold-plating." Under rate-of-return regulation, regulated monopolies have no incentive to minimize their capital purchases, since prices are set equal to their costs of production.

Rate-of-return regulation was dominant in the US for a number of years in the government regulation of utility companies and other natural monopolies. Such companies, if not regulated, could easily charge far higher rates since consumers would pay any price for essential goods such as electricity or water.