When shopping for a mortgage, the lender may give you a quote for the mortgage interest rate and points (additional fees charged by the lender usually paid at closing by the borrower). These only represent terms available at the time of the quote. They may not be available by the closing date (which may be weeks or months in the future). To ensure the rate and points are the same at closing as they are when quoted, you'll need to lock-in the interest rate (also known as a rate lock or rate commitment).