Rates & interest
Rate lock
A lender's guarantee to hold a quoted interest rate for a set period — often 30 to 60 days — while your loan closes, protecting you from rate increases in the meantime.
What does rate lock mean?
Because mortgage rates move daily, a rate lock freezes your quoted rate so a market swing between application and closing can't raise your payment. Locks typically run 30 to 60 days; longer locks or extensions can cost more.
If rates fall after you lock, some lenders offer a one-time float-down.
Why it matters
A Michigan purchase often takes 30 to 45 days from accepted offer to closing — right inside the standard lock window. Locking at application is what makes the rate you were quoted the rate you actually get.
If your closing slips past the lock's expiration, you may face a costly extension fee or a re-lock at whatever the market offers that day. Watching the calendar is part of protecting the rate.
Common questions
What if rates drop after I lock?
You're generally held to the locked rate, though some lenders offer a one-time float-down that lets you capture a lower rate once before closing. Ask before you lock.
Related terms