Suppose you are buying with a $400,000 loan on a 30-year fixed mortgage. At 6.50%, the principal and interest payment is about $2,528 a month. If the market moves and your rate becomes 7.00% before closing, the payment rises to about $2,661, roughly $133 more each month and nearly $8,000 over five years. These figures are illustrative, not a current quote. A rate lock exists to prevent that kind of surprise.
A mortgage rate lock is a lender’s written promise to hold your interest rate for a set number of days while your loan is processed and closed. It does not guarantee approval, and its terms and costs vary by lender. In this article, Duane Buziak, NMLS #1110647, explains how locks work, what lock periods cost, how float-down options and extensions compare, when to lock, and what happens if a lock expires.
- How a Rate Lock Works From Application to Closing
- Lock Periods and What They Cost
- Float-Down Options and Lock Extensions Compared
- When to Lock Your Rate and When Floating Makes Sense
- What Happens If Your Lock Expires or Your Loan Changes
- Rate Lock Questions Buyers Ask Most
- Matching the Lock to Your Real Closing Date
How a Rate Lock Works From Application to Closing
A few terms come up repeatedly. The rate lock (sometimes called a rate lock agreement) is the commitment itself. The lock period is the number of calendar days it lasts. The locked rate is the rate the lender has committed to, while a quoted rate is only an estimate of what is available today. Your Loan Estimate states whether your rate is locked, and the Consumer Financial Protection Bureau explains how to read it. The CFPB also has a plain-language page on what a mortgage rate lock is.
The sequence is usually straightforward:
- You choose a loan program and a rate and points combination.
- Your loan officer submits a lock request to the lender.
- The lender confirms the lock in writing, with the rate, the lock date, and the expiration date.
- The clock runs in calendar days, weekends included, until you close.
A quote is not a lock. Receiving a Loan Estimate does not mean your rate is held, and many borrowers assume otherwise. Most lenders also require an active application and an identified property before they will lock, which is why a buyer still house hunting often cannot lock yet.
The lock protects the interest rate and, typically, the points or lender credits tied to that rate. It does not protect your approval. Your credit, income, assets, and the appraisal still have to hold up through underwriting. A locked rate on a loan that does not close is worth nothing.
Lock Periods and What They Cost
Common lock lengths are 30, 45, and 60 days, though lenders offer other options. As of 2026, longer locks are often priced slightly higher because the lender carries the market risk for more time. Exact pricing differs by lender, loan program, and day, so treat any number you see online as a starting point and ask for yours in writing.
Closing timelines drive the choice. A resale purchase with a 30-day contract may fit a 30 or 45-day lock. New construction often needs longer, since completion dates can slip. If a closing runs past the lock, an extension is usually available, typically priced per day or as a percentage of the loan amount. A lock that is a little longer than you need often costs less than an extension later, but compare both.
| Lock Length | Typical Use Case | Pricing Tendency | Risk of Expiring |
|---|---|---|---|
| 30 days | Resale purchase with a short contract and a clean file | Usually the lowest cost of the common options | Higher if the appraisal, title, or documents are delayed |
| 45 days | Standard purchase or refinance with some timing cushion | Often slightly above a 30-day lock | Moderate |
| 60 days | Longer closings, new construction, or complex files | Often priced higher than shorter locks | Lower, though construction delays can still outrun it |
| Extension | Closing slips past the original lock date | Typically charged per day or as a percentage; verify current terms | Covers the gap, but adds cost |
Lenders also differ on how they charge. Some assess a separate lock fee, while many build the cost of the lock into the interest rate or the points. Neither approach is automatically cheaper, so you need to see the full picture. Ask for the lock terms, any fee, and the extension pricing in writing before you commit.
Float-Down Options and Lock Extensions Compared
A float-down is a one-time option to reset your locked rate to a lower market rate if rates fall. It usually comes with a fee, or it requires that rates drop by a minimum threshold before it can be used. Both the fee and the threshold vary by lender. A lock extension is different: it adds days when closing slips past your lock date, and it is typically charged per day or as a percentage of the loan. Verify the current terms with your lender, because both are set by policy rather than by rule.
Here is an illustrative float-down comparison. Suppose you lock a $400,000 loan at 6.75%, where the payment is about $2,594. A float-down later resets you to 6.50%, or about $2,528, saving roughly $66 a month. If the option cost $2,000, you would need about 30 months to recoup it. If you expect to sell or refinance sooner, the float-down may never pay for itself. The numbers are hypothetical, not an offer.
Large lenders handle locks differently, and you should confirm each lender’s terms directly. On structure only:
- Rocket: sets its own lock periods, fees, and extension terms. Check its site or your loan documents for current policy.
- Movement: likewise sets its own terms, so ask for them in writing.
- Veterans United: also sets its own lock policy. Confirm details with the lender, because they can change.
No federal rule sets standard lock fees or float-down terms, which is why identical-looking rates can come with very different lock conditions. Compare the terms, not just the rate.
When to Lock Your Rate and When Floating Makes Sense
Mortgage rates move with the bond market, and nobody reliably times them. Freddie Mac publishes weekly averages in its Primary Mortgage Market Survey. Check the latest 2026 reading when you decide, and remember that it reports a national average as of that week, not the rate you will be offered.
Three factors usually decide the question:
- Time to closing: the closer you are, the less there is to gain by waiting.
- Payment cushion: if your debt-to-income ratio is already near the limit for your program, a small rate rise could jeopardize approval.
- Risk tolerance: if a $66 monthly swing would cost you sleep, lock.
Many buyers lock at contract, or once the appraisal and underwriting timeline is clear. Locking late has its own hazard: if you wait for a dip that never arrives, you carry the full exposure right up to closing.
Consider a short scenario on a $400,000 loan. If you float and the rate rises from 6.50% to 6.75%, your payment goes up about $66 a month, roughly $3,970 over five years. If it falls by the same amount, you save the same. Floating is a coin flip with an uneven consequence: a rise can push you past your qualifying limit, while a drop is only a bonus. Locking trades the upside for certainty.
Before you lock, compare quotes. The rate you lock matters more than the timing of the lock. Duane Buziak, as an independent consultant, compares pricing across hundreds of wholesale lenders. The comparison is free and does not hit your credit, so you can find the strongest option first and then lock it.
What Happens If Your Lock Expires or Your Loan Changes
If a lock expires before closing, the outcome depends on lender policy. Commonly the lender reprices the loan at the current market rate, or at the worse of your original and the current rate. Some allow an extension for a fee if you ask before the expiration date. After it passes, you have less leverage.
Delays usually come from a handful of causes:
- Appraisal problems, including a low value or required repairs
- Title issues such as liens or ownership questions
- Missing or outdated documents
- A late change in your income or credit picture
Some changes can alter a locked deal even before it expires. Switching the loan program, changing the loan amount, a different occupancy (primary residence versus investment property), or a change in property type may require a reprice. A credit score that falls below a pricing tier can also change the terms, since the lock is built on the profile you applied with. Avoid new credit accounts and big purchases until you close.
A few practical steps lower the risk:
- Ask for a realistic closing timeline when you lock, and pick a lock period with some cushion.
- Keep pay stubs, bank statements, and other documents current, and respond to requests quickly.
- Request a written extension quote before the lock date runs out, not after.
Rate Lock Questions Buyers Ask Most
Is a mortgage rate lock free?
Sometimes. Some lenders charge a separate lock fee, while many build the cost into the rate or points. Longer locks and extensions typically cost more. Ask for the lock cost in writing so you can compare offers on equal terms.
Can I lock a rate before I have a purchase contract?
Often not. Most lenders require an active application and an identified property before they will lock. Without a property address, you can usually get a preapproval and a rate quote, but the quote is not held and can change.
How long should I lock my mortgage rate for?
Match it to your realistic closing date, plus a small cushion. Thirty to 45 days commonly fits a resale purchase, while new construction may need 60 days or more. A lock slightly longer than needed often costs less than an extension.
Can I lock a rate for a refinance?
Yes. Refinances can be locked once you have an application and the property is identified, since it is your current home. Lock periods and pricing work much the same way as for a purchase, though terms vary by lender.
Can my rate go up after I lock?
Market movement cannot change a valid lock. Your rate can still be repriced if the lock expires, or if the loan changes, such as a different loan program, loan amount, occupancy, or a credit score that falls below a pricing tier.
What if rates drop after I lock?
You generally keep your locked rate, even though the market is lower. A float-down option, if your lender offers one, may allow a one-time reset, usually for a fee or a minimum rate drop. Ask about it before you lock, because it is rarely available afterward.
Does locking a rate affect my credit?
No, the lock itself does not. Credit inquiries come from the mortgage application and credit pull, not from the lock. Comparing rates through Duane Buziak does not hit your credit. Just avoid opening new accounts before closing, since a score drop can change your pricing.
Can I switch lenders and keep my lock?
No. A lock is a commitment between you and a specific lender for a specific loan. If you move to another lender, you generally need a new lock at that lender’s current pricing, which is why comparing before you lock matters.
Is a rate lock the same as a preapproval?
No. A preapproval estimates how much you may qualify to borrow, based on your documents. A lock holds a specific rate for a set period on a specific loan. You can be preapproved without a lock, and a lock does not guarantee approval.
What is a lock extension fee?
It is what a lender charges to add days when closing slips past your lock date. It is typically priced per day or as a percentage of the loan amount, and it varies by lender. Get the quote in writing before the original lock expires.
One state data point: Virginia loans follow the conforming loan limits that the Federal Housing Finance Agency sets each year. For 2026, the baseline one-unit limit is $832,750 as of FHFA’s annual announcement, with higher limits in designated high-cost areas such as parts of Northern Virginia. Confirm your county’s figure on the FHFA website, since limits can differ by county.
Matching the Lock to Your Real Closing Date
A rate lock is a time-limited promise, so the useful question is how long you actually need it. Pick the lock period that fits your realistic closing date with a small cushion, get the lock cost and extension terms in writing, and compare quotes before you commit to a lender.
Ready to secure a competitive mortgage rate for your Virginia home without impacting your credit score? Get your free personalized rate comparison from an independent consultant recognized as one of Virginia’s top loan officers, with no obligation and no hidden fees. Duane Buziak at Grand Rates by Duane Buziak can compare options across hundreds of wholesale lenders before you lock.
