Yes. Obtaining a mortgage rate lock as soon as you have an accepted offer on a house (and find a rate you're comfortable with) can help guarantee a competitive rate and affordable monthly payments on your loan. A rate lock means that your lender will guarantee your agreed-upon rate, typically for 45 to 60 days, regardless of market fluctuations. Ask your lender about "float-down" options as well, which allow you to snag a lower interest rate if average rates drop during your lock period. This option usually comes with a fee that ranges between 0.50% and 1% of the loan amount.