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. The practical lesson for Michigan buyers: once you've shopped and found a competitive quote, lock it — chasing a lower rate while unlocked exposes you to the opposite move.
Common questions
How long does a rate lock last?
Typically 30 to 60 days — long enough to close. Longer locks or extensions usually cost more, and blowing past the lock can force a costly re-lock at current rates.
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.
When should I lock my rate?
Once you've shopped and found a competitive quote and you're within the lock window of closing. Staying unlocked to chase a lower rate exposes you to the opposite move.
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