Rate Lock
Direct definition
A lender's guarantee that your interest rate won't change for a set period before closing.
Written by the Vabasso Mortgage Editorial Team · Reviewed against agency and federal sources · Read our editorial policy for how we research and review mortgage content
Plain-English explanation
A lock protects you from rising rates during processing. Longer locks and float-down features usually cost more.
Why it matters
Timing the lock right can save real money — and a lock protects you from mid-process shocks.
Where you may see it
- Rate lock confirmation
- Loan Estimate
- Closing Disclosure
A real-world example
You lock a 6.50% rate for 45 days after the appraisal is ordered; even if rates rise, your rate stays 6.50%.
Educational and illustrative only
A common misunderstanding
A rate lock isn't permanent or unconditional — it usually has an expiration date, and changes to the loan can require re-locking or extending at a cost.
Ask Vabasso AI
This glossary provides general educational information. Mortgage terminology, qualification methods, forms, timelines, fees, program rules, and legal meanings may vary by lender, investor, loan program, property, occupancy, state, and transaction. Definitions do not represent loan approval, legal advice, tax advice, or a commitment to lend.
- Author
- Vabasso Mortgage Editorial Team
- Reviewed by
- Vabasso Mortgage Licensed Advisory Team
- Last reviewed
- July 30, 2026