Rates & Loans
What is a mortgage rate lock?
Updated Jul 1, 2026
The short answer
A rate lock is a lender’s guarantee to hold a specific interest rate for a set window — commonly 30 to 60 days — while your loan is processed, protecting you if market rates rise before closing. If rates fall during the lock, you generally keep the locked rate unless your lock includes a float-down option. Locks that expire before closing may need a paid extension.
Key points
- Locks hold your rate for a defined period (often 30–60 days).
- Protects you from rate increases before closing.
- A float-down option lets you capture a drop, sometimes for a fee.
Timing the lock
Locking too early risks expiration before closing; locking too late risks a rate move. Coordinate the lock window with your expected closing date, and get the terms in writing.
Sources
Every claim above traces to a public government source.
- ViewT1What is a mortgage rate lock?
Consumer Financial Protection Bureau · Government / primary · 2024