What Is a Mortgage Rate Lock?
A mortgage rate lock is a lender's commitment to hold a specific interest rate for a set period, commonly 30 to 60 days, while a loan is processed. If rates rise during the lock, the locked rate still applies; if the lock expires before closing, the rate may change.
Lock Terms
Longer locks may cost more, and extending an expired lock can involve a fee. Some locks include a float-down option that allows a lower rate if market rates fall, usually for a fee.
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🔗 Related Terms
More Home Buying Terms
- Adjustable-Rate Mortgage (ARM)
- Appraisal Gap
- Assessed Value
- Bridge Loan
- Cash-Out Refinance
- Closing Disclosure
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Last updated: September 27, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.