A conforming loan is a mortgage that is equal to or less than the loan limit set annually by Fannie Mae or Freddie Mac, the government-sponsored agencies that purchase the bulk of U.S. residential mortgages from banks and other lenders. The current conforming loan limit for a single-family home or condominium in most areas of the country is $453,100 (2018), with higher limits allowed for designated high-priced markets.

The terms conforming and conventional are often used interchangeably. Mortgage loans that are higher than the conforming loan limit are called jumbo mortgages or nonconforming loans.