A rate "lock" or "commitment" is a lender's promise to lock in a specific interest rate and a certain number of points for you for a specified period during your application process. This ensures that your interest rate can't rise as you are going through the application process.
Rate lock periods can vary in length, between fifteen to sixty days, with the longer period typically costing more. You can get a longer period for your lock, but in choosing this option, will probably have a higher interest rate than you would have with a shorter rate lock period
In addition to opting for the shorter lock period, there are other ways you are able to attain the lowest rate. A bigger down payment will result in a reduced interest rate, since you'll be starting out with a good deal of equity. You could opt to pay points to bring down your rate for the loan term, meaning you pay more initially. To many people, this is a good option..
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