FAQ
What does locking my interest rate mean?
Quick Answer
Locking your rate means your lender guarantees a specific interest rate for a set period — commonly 30 to 60 days — while your loan moves through processing, protecting you if rates rise during that window. If rates drop after you lock, you generally can't take advantage of the lower rate without paying a fee for a 'float-down,' if your lender even offers one. Rate locks typically have an expiration date, so timing your lock to your expected closing date matters.
Key Takeaways
- A rate lock guarantees your interest rate for a specific window, commonly 30 to 60 days, while your loan is processed.
- Locking protects you from rate increases during that window, but usually means you can't benefit from a rate decrease without a fee.
- Some lenders offer a 'float-down' option for a fee, letting you capture a lower rate if rates drop after you lock — ask if this is available.
- Rate locks expire on a specific date — if your closing is delayed past that date, you may need to pay an extension fee or re-lock at current rates.
- Timing your lock closer to your expected closing date reduces the risk of needing an extension.
Rate locks are one of those mortgage terms buyers hear constantly during the process but rarely have explained clearly before they need to make a decision about one.
What a Rate Lock Actually Does
When you lock your rate, your lender commits to a specific interest rate for a defined window of time — commonly 30 to 60 days, sometimes longer for new construction. During that window, your rate won't change even if broader market rates move up.
A lock is a commitment, not just a quote
Before locking, any rate your lender quotes is essentially an estimate that moves with the market. Once locked, that specific rate is guaranteed for the agreed window, assuming your loan terms don't change.
Why Locking Usually Only Protects You One Direction
30–60 days
Typical Lock Window
Rate increases during the window
Protects Against
Usually not captured without a fee
Rate Decreases
Sometimes available — ask your lender
Float-Down Option
If market rates rise after you lock, you're protected — you keep your locked rate. If rates fall after you lock, you generally can't take advantage of the improvement unless your lender specifically offers a float-down option, which typically comes with its own fee.
Dave's Local Insight
I always ask lenders on my clients' behalf whether a float-down option exists before locking, especially in a period where rates seem to be trending down. It's a simple question that can save real money.
What Happens If Your Closing Gets Delayed
Rate locks have a hard expiration date. If your closing slips past that date — due to an inspection negotiation, appraisal delay, or any other holdup — you may need to pay an extension fee, or in some cases re-lock at the current market rate, which could be higher or lower than your original lock.
How to reduce rate-lock timing risk
- Time your lock as close to your realistic closing date as your lender allows
- Ask what the extension fee structure looks like before you lock, in case of delays
- Confirm whether a float-down option exists and what it costs
- Keep your lender updated on any changes to your expected closing timeline as soon as you know about them
A Simple Way to Think About Timing Your Lock
Do you expect rates to be volatile or trending upward before your closing?
Yes
Locking sooner protects you from a rate increase during your loan's processing period.
No
You may have more flexibility on timing, but confirm your lock window still comfortably covers your expected closing date.
Bottom Line
Locking your rate guarantees a specific interest rate for a set window while your loan processes, protecting you from increases during that time but usually not allowing you to benefit from a later decrease without a float-down fee. Because locks expire on a specific date, timing your lock to your realistic closing date — and asking about extension and float-down policies up front — avoids most of the friction buyers run into with this step.
Related Questions
Sources
Written by Dave Brown
REALTOR®, LPT Realty
Dave Brown is a REALTOR® with LPT Realty who has spent his career helping families buy, sell, and settle into life in Woodbury, Minnesota and the surrounding East Metro. He writes Woodbury Living as a local resource first and a business second — every guide is meant to leave you better informed, whether or not you ever work together.
Need help buying or selling in Woodbury?
Book a no-pressure consultation with Dave to talk through your specific situation — no obligation, just straight answers.