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1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsA mortgage rate lock holds the interest rate and, generally, the points quoted by your lender for a specified period. The protection is conditional: you must close before the lock expires and your application must remain materially unchanged. If rates rise, a valid lock can protect your quote; if rates fall, you usually remain at the locked rate unless your agreement includes a float-down or the lender offers another option. Before locking, get the duration, all fees, extension terms, float-down rules, and the consequences of a delayed closing in writing.
What is a mortgage rate lock?
The Consumer Financial Protection Bureau (CFPB) defines a lock-in or rate lock as an agreement that your interest rate will not change between the offer and closing, provided you close within the specified time and there are no changes to your application. In practice, the lock is a time-limited, conditional promise—not a guarantee that survives every underwriting or closing problem.
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Common periods are 30, 45, or 60 days, with some lenders offering longer periods. Freddie Mac describes 30- and 45-day periods as most common and also discusses 60- and 90-day options. Availability, pricing, and eligible loan products are lender-specific. The period should be long enough to cover your expected closing date plus a realistic delay buffer, but a longer period may carry a higher fee or rate.
What a lock protects
- The quoted interest rate, if the lock conditions are satisfied.
- The quoted discount points or lender credits, subject to the written agreement and permitted changes.
- Your ability to plan a principal-and-interest payment using the locked rate.
What a lock does not protect
- A closing date that slips beyond the expiration date.
- Terms affected by a material change in the loan application.
- Every closing cost. Settlement-charge tolerance rules differ by fee category and have exceptions.
- A lower market rate, unless a float-down or a new lock is available under your agreement.
How much does a rate lock cost?
There is no nationally established consumer price for a rate lock in the reviewed CFPB and Freddie Mac guidance. A lender may charge a separate lock fee, build the cost into the interest rate or points, or offer a particular period without a separately identified charge. The Loan Estimate indicates whether the rate is locked and the length of the lock, but it does not state the price of the lock period, the cost to extend it, or whether another period costs more or less.
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Ask the lender to identify every amount associated with each lock choice. Request the answer in writing rather than relying on a verbal quote that could be misunderstood later.
- Is there an upfront lock fee?
- Is it refundable if the loan is denied, the purchase contract ends, or you switch lenders?
- Are points, lender credits, or other pricing adjustments different for a 30-, 45-, 60-, or longer lock?
- Does the fee apply once, or can it be charged again after an extension or relock?
- What event starts the lock clock: application, approval, disclosure, or another date?
How to choose a lock period
Compare the period with the transaction’s actual timetable, not an optimistic target. A purchase with an appraisal, title work, loan conditions, and a long chain of sellers may need more time than a straightforward refinance. Freddie Mac identifies market conditions, proximity to closing, and your comfort with interest-rate risk as relevant considerations.
| Choice | Potential advantage | Risk or cost to investigate |
|---|---|---|
| Shorter lock | May have lower pricing and leaves more opportunity to benefit from falling rates before locking. | Greater chance of an expiration, extension fee, or relock if closing is delayed. |
| Longer lock | Provides more time for underwriting and closing contingencies. | May carry a higher rate or fee, and you may be committed to a higher rate if the market falls. |
| Lock later | Keeps the rate floating while you wait for a clearer closing date. | Rates can rise before you lock, increasing the payment or required cash. |
Make offers comparable before deciding. A 30-day quote with one set of points cannot be fairly compared with a 60-day quote using different points, a different loan type, or a different down payment assumption.
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Contact the lender before the expiration date. Do not assume the lock extends automatically or that the original rate will be preserved without a written amendment.
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- Ask whether the existing lock can be extended and identify the proposed new expiration date.
- Request the exact extension fee, how it is calculated, when it is due, and whether it is refundable.
- Confirm whether the extension preserves both the rate and points or changes either one.
- Ask what happens if the lender declines an extension or the closing misses the new date.
- Obtain the extension terms and any revised disclosures in writing.
The CFPB does not publish a standard consumer extension amount. The answer depends on the lender, loan, remaining time, and contract. A lender may instead let the lock expire and offer a new market lock; that can produce a different rate, points, and fee.
Disclosure treatment for a requested extension
Under the official Regulation Z interpretation of 12 CFR § 1026.19, a creditor may issue revised disclosures to reflect a new rate-lock extension fee when the consumer requested the extension. The fee may not exceed the fee the creditor charges in the usual course of business. This rule governs how the fee is disclosed; it is not a national price schedule and does not guarantee that an extension will be approved.
A program-specific rule is not a universal consumer right
Fannie Mae’s Section 305, effective May 20, 2026, addresses certain streamlined rate-lock mortgage loans in its multifamily seller/servicer guide. It requires full underwriting and compliance with modification requirements before specified rate-lock and commitment expiration dates can be extended. That is an institutional rule for a defined multifamily program, not a promise that a consumer’s lender must extend a residential lock.
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What happens if mortgage rates fall after you lock?
Absent a contractual float-down or a new agreement, the lender generally funds the loan at the locked rate even if market rates fall. This is the trade-off for protection against rising rates. Ask whether the lender permits a relock, but do not assume a lower rate advertised later automatically changes your existing lock.
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Can you get a float-down?
A float-down is a lender-dependent feature that may allow you to receive a lower rate that becomes available during the lock period. Freddie Mac notes that some lenders offer it and that the terms vary. It is not universal, and a lender’s ordinary rate sheet does not by itself establish that your locked loan qualifies.
Before locking, ask for written answers to each of these questions:
- Is a float-down included, or can it be added after the initial lock?
- When may it be exercised—once, at a specific stage, or at any point before closing?
- How far must the market rate fall, and which comparable rate is used?
- Is there a fee, a higher initial rate, additional points, or another charge?
- How many exercises are permitted?
- After exercise, what are the final rate, points, lender credits, and expiration date?
- Does exercising the option require a new approval, updated disclosures, or a new appraisal?
Do not insert a threshold or fee into your calculations unless it appears in your own agreement. Two lenders can use the term “float-down” for materially different provisions.
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A lock does not freeze the application. CFPB examples of changes that can affect the rate or eligibility include:
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- A different loan amount, loan type, or down payment.
- A credit-score change caused by new debt, a missed payment, or another event.
- An appraisal that is higher or lower than expected.
- Income that cannot be documented, including overtime or bonus income.
- Other underwriting facts that change the lender’s risk or the program’s requirements.
Tell the lender promptly about changes rather than making a large purchase, opening credit, changing jobs, or moving money without understanding the underwriting effect. A lender may need to reprice or re-underwrite the loan; the exact outcome is controlled by the lock agreement and applicable program rules.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What if the Closing Disclosure differs from the Loan Estimate?
Compare the Closing Disclosure with the Loan Estimate and the rate-lock confirmation as soon as you receive them. If the rate, points, or fees differ, ask the lender for a specific written explanation tied to the change.
With a rate lock, CFPB guidance says the rate and points generally should not change unless an exception applies. A changed loan application, appraisal, or income verification can be an explanation. Settlement costs are governed by tolerance categories: some may increase by any amount, some generally cannot increase without a qualifying change in circumstances, and certain categories are subject to an aggregate 10 percent limit. The 10 percent tolerance is not a cap on all closing costs and does not automatically cap a rate-lock extension fee.
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If the explanation is not satisfactory, ask the lender to correct an apparent error before closing. CFPB notes that a borrower may consider another lender and may have rights when a change was illegal. Individual disputes can involve contract and regulatory questions for which qualified legal advice may be appropriate.
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Rate-lock comparison checklist
Use the same assumptions for every quote and record the answers in one place.
| Item | What to record |
|---|---|
| Timing | Lock start date, expiration date, expected closing date, and realistic delay risk. |
| Pricing | Interest rate, points, lender credits, lock fee, and whether any fee is refundable. |
| Extension | Exact fee, calculation method, approval process, new expiration date, and whether rate and points remain unchanged. |
| Float-down | Availability, trigger, exercise window, fee or rate premium, number of exercises, and post-exercise terms. |
| Loan assumptions | Loan type, amount, down payment, credit assumptions, property type, and occupancy. |
| Documents | Rate-lock agreement, Loan Estimate, revised disclosures, and Closing Disclosure. |
Practical questions borrowers commonly ask
“What’s a lock-in or a rate lock on a mortgage?”
It is a time-limited agreement to hold the quoted rate, usually subject to closing within the stated period and no material application changes.
“What if my closing is delayed and the rate lock expires?”
Call the lender before expiration and obtain written extension terms, including the fee, new date, and effect on rate and points. If no extension is available, the loan may need a new lock at then-current pricing.
“If I lock my rate, and interest rates go down, what happens?”
You generally keep the locked rate rather than receiving the lower market rate. A float-down or other written relock provision is the exception.
How should I estimate the payment impact?
You can use a basic mortgage calculator to compare payment scenarios, but it is optional and cannot establish your lender’s rate, points, extension fee, or float-down terms. Use the lender’s written figures for the final comparison.
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