A mortgage broker acts as an intermediary who brokers mortgage loans on behalf of individuals or businesses.

Traditionally, banks and other lending institutions have sold their own products. As markets for mortgages have become more competitive, however, the role of the mortgage broker has become more popular. In many developed mortgage markets today, (especially in the United States, Canada, the United Kingdom, Australia, New Zealand, and Spain), mortgage brokers are the largest sellers of mortgage products for lenders.

Mortgage brokers exist to find a bank or a direct lender that will be willing to make a specific loan an individual is seeking. Mortgage brokers in Canada are paid by the lender and do not charge fees for good credit applications.

In the US, many mortgage brokers are regulated by their state and by the CFPB to assure compliance with banking and finance laws in the jurisdiction of the consumer. The extent of the regulation depends on the jurisdiction.