What Is a Mortgage Rate Lock and How Long Does It Last in California?
If you have ever been mid escrow and heard your loan officer say "we need to lock your rate today," you already know how stressful that sentence can feel. What does locking actually mean, and what happens if your closing gets pushed back?
Quick answer: a rate lock freezes your interest rate for a set period, typically 30, 45, or 60 days in California, so it does not move while your loan is being processed. If your closing happens within that window, the rate you locked is the rate you get, regardless of what the market does in the meantime. If you go past the lock period, you may need an extension, which can cost money or, in some cases, be free depending on your lender and the reason for the delay.
I am Katrina Carter, a real estate broker and loan officer in San Leandro, and rate locks come up in almost every purchase and refinance conversation I have. It is one of those pieces of the process that sounds simple until you are the one living through it, so I want to walk through it plainly.
1. What a Rate Lock Actually Does
When you lock your rate, your lender is committing to that specific interest rate for a defined window of time, no matter what happens in the bond market between now and your closing date. Without a lock, your rate is "floating," which means it can move up or down daily based on market conditions until you decide to lock it in.
2. When Locks Typically Happen
Most buyers lock once they are in contract and have a firm closing date, because the lender needs to know the actual number of days between locking and funding. Common lock periods in California are:
15 days, for very fast closings
30 days, the most common for a standard purchase
45 days, often used when there is more uncertainty in the timeline
60 days, common for new construction or longer escrows
Shorter locks generally come with slightly better pricing because there is less risk for the lender, while longer locks cost a little more because the lender is protecting you against a longer window of market movement.
3. What Happens If Your Closing Gets Delayed
This is the part that catches people off guard. If your escrow runs past your lock expiration, for example because of an appraisal delay, a title issue, or a seller who needs a few extra days, you will likely need a lock extension. Depending on your lender, this might be:
Free, if the delay was on the lender's side or minor
A small fee, often a fraction of a percent of the loan amount
A repricing to current market rates, in rare cases with certain lenders
This is exactly why I encourage clients to build in a few extra days of cushion when possible, rather than locking the absolute minimum period.
4. Can You Lock Too Early?
Yes, in a sense. If you lock before you are fully in contract, or before your closing date is realistic, you risk running out the clock and needing an extension anyway. On the flip side, floating too long into a rising rate environment can mean your final rate is worse than what was available earlier. There is a balance, and it usually comes down to timing the lock once your purchase agreement and closing date are solid.
5. What About Rate Locks During a Refinance?
The same principles apply, but refinances sometimes have more flexibility on timing since there is no seller or closing deadline dictated by another party. Even so, I recommend locking once you have decided to move forward, rather than trying to perfectly time the market, because predicting daily rate movement is nearly impossible even for professionals.
6. Float Down Options
Some lenders offer a "float down" option, which allows you to lock a rate but still benefit if rates drop significantly before closing. This typically comes with an added cost or a specific set of conditions, so it is worth asking your loan officer directly whether this is available and whether it makes sense for your situation.
After 24 years in East Bay real estate, one thing I see consistently is buyers who assume the rate they saw advertised online is automatically what they will get. The truth is that your actual locked rate depends on your credit profile, your loan type, your closing timeline, and the day you choose to lock. This is why working with a local loan officer who is tracking your file in real time matters more than a number on a website.
FAQ
Does locking my rate cost extra money?
In most cases, a standard lock period is built into your loan pricing at no additional charge. Extended locks, like 60 or 90 days, sometimes carry a small cost, which your loan officer can confirm upfront.
Can I lock my rate before I find a home?
Generally no, because most lenders require an active purchase contract with an address and closing date before locking. Some limited "lock and shop" programs exist, but they are not universal.
What if rates drop after I lock?
Unless you have a float down option built into your loan, you will keep the rate you locked even if rates drop afterward. This is the tradeoff for the protection a lock provides if rates rise instead.
Can my rate change after locking if my credit score changes?
Yes. If your credit score drops significantly, or your financial picture changes materially before closing, your lender may need to reprice your loan even with a lock in place. This is why I always tell clients to avoid new credit inquiries or large purchases during escrow.
If you are getting ready to buy or refinance in San Leandro or anywhere in the East Bay and want a clear walkthrough of how rate locks, timing, and your specific numbers work together, I am happy to talk it through with you.
Katrina Carter
Broker Associate | Loan Officer
Call or text: 510.288.6002
