Mortgage Rate Lock: When to Lock, How Long It Lasts, and What It Costs
A mortgage rate lock is a written agreement from a lender that holds your interest rate steady for a set number of days while your loan moves to closing. If rates rise during that window, you keep your locked rate. If rates fall, you typically stay locked unless your agreement includes a float down option.
This guide breaks down how rate locks work, how long you can lock a mortgage rate, when locking makes sense, and what New Hampshire buyers should know before signing. By the end, you will know exactly how to talk to your lender about locking and how to avoid the most common mistakes that cost borrowers money.
What Is a Mortgage Rate Lock?
A mortgage rate lock is a commitment between you and your lender that freezes your interest rate, points, and lender fees for a defined period, usually between 15 and 90 days. The lock protects you from market volatility while underwriting, appraisal, and closing happen.
Quick answer: A rate lock is not a loan approval. It is a price guarantee tied to a specific loan scenario (loan amount, property, credit profile, and program). If any of those change, the lock can be repriced or voided.
According to the Consumer Financial Protection Bureau (CFPB), lenders are required to disclose whether your rate is locked or floating on your Loan Estimate. If you see "NO" in the rate lock box, your rate can still change before closing.
What a rate lock covers
The interest rate quoted on your Loan Estimate
Discount points if you chose to buy down the rate
Lender origination fees tied to that pricing
What a rate lock does not cover
Third-party fees (appraisal, title, recording)
Property taxes and homeowners insurance
Changes you make to the loan (different program, lower down payment, longer term)
How Long Can You Lock a Mortgage Rate?
Standard rate lock periods in 2026 range from 15 to 90 days, with 30, 45, and 60 days being the most common. Longer lock periods give you more cushion but cost more in pricing.
Here is how typical lock periods compare:
Some lenders offer extended locks of 120 to 360 days for new construction. These are useful when a home will not be ready for months, but they carry meaningful pricing penalties and often require a non-refundable deposit.
A NextGen broker can run pricing across multiple lenders for the same lock length, so you can see exactly what each day of protection costs before you commit.
When to Lock in Mortgage Rate
The right time to lock depends on three things: how rates are trending, how close you are to closing, and how much volatility your budget can absorb. Most borrowers should lock once they have a fully ratified purchase agreement and an underwriting timeline they trust.
Lock when these conditions are true
You have a signed purchase contract or refinance application in process
Your loan estimate matches your monthly payment expectations
You can close within the lock window your lender offers
Rates are stable or trending up, and you cannot afford a higher payment
Consider waiting if these are true
Closing is more than 60 days out and lock pricing is expensive
The Federal Reserve is signaling a near-term rate cut and your budget has room to absorb a small increase
Your loan file has open issues that could push closing past the lock expiration
Watch the rate environment
The Freddie Mac Primary Mortgage Market Survey (PMMS) publishes weekly average rates every Thursday. It is the most widely cited benchmark for 30-year fixed mortgage rates in the United States. Tracking it for two or three weeks before you lock gives you a feel for whether rates are climbing, falling, or moving sideways.
That said, no one consistently times the bottom of the market. If a current rate works for your budget and you are inside your closing window, locking removes a major source of stress.
What Is a Float Down Option Mortgage?
A float down option mortgage lets you lock your rate but capture a lower one if market rates drop by a defined amount before closing. It is a hedge that protects you from both rising rates and the regret of locking too early.
How float down options typically work
You lock at today's rate for the standard period
If market rates fall by a minimum threshold (often 0.25% or more) before a deadline, you can request the lower rate
The float down can usually be exercised once
Lenders charge a fee or build the cost into your pricing
When a float down makes sense
A float down is most valuable when rates are volatile and you want to lock in case they spike, but you also believe a meaningful drop is plausible before closing. If rates have been flat for weeks, paying for a float down often does not pay off.
Not every lender offers float downs, and the terms vary widely. Working with a broker means you can compare which lenders include the option, how much it costs, and what the qualifying drop must be. Speak with a NextGen broker to see which lender pricing fits your timeline and risk tolerance.
What Happens If Your Rate Lock Expires?
If your mortgage rate lock expires before closing, you have three options, and none of them are free. This is one of the most common ways borrowers lose money in the closing process.
Option 1: Extend the lock
Most lenders allow extensions in 7, 10, or 15 day increments. The cost is typically charged as a small percentage of the loan amount or as additional pricing baked into the rate. Extension fees often range from 0.125% to 0.25% of the loan amount per extension.
Option 2: Relock at current market rates
If rates have moved up, relocking can mean a significantly higher payment. On a $400,000 loan, a 0.5% rate increase adds roughly $115 to your monthly principal and interest payment, which is more than $40,000 over a 30-year term.
Option 3: Worst case relock
Some lenders apply a "worst case" pricing rule when a lock expires, meaning you get the higher of the original locked rate or the current market rate. This protects the lender, not you.
The cleanest way to avoid lock expiration is realistic timeline planning at the start. Conventional purchase loans in New Hampshire typically close in 30 to 45 days. VA and FHA loans can take 45 to 60 days due to appraisal requirements. New construction varies wildly.
How Much Does a Mortgage Rate Lock Cost?
For most loans, the lock itself does not have a separate line item fee. The cost is built into your rate. A 60-day lock will be priced slightly higher than a 30-day lock for the same loan, even though no upfront cash changes hands.
Direct fees show up in three situations:
Extended locks (90+ days), often used for new construction, may require a deposit of 0.5% to 1% of the loan amount, sometimes credited at closing
Lock extensions when the original window expires
Float down activation fees if you exercise the option
The CFPB requires lenders to disclose these costs on the Loan Estimate. If something is unclear, ask for a written breakdown before you commit.
Mortgage Rate Lock Considerations for New Hampshire Buyers
New Hampshire's housing market has its own rhythms that affect when and how to lock a rate. Closings here are influenced by appraisal turn times, the prevalence of older housing stock, and seasonal inventory swings.
NH-specific factors that affect lock timing
Older homes need careful inspection windows. Much of NH's housing stock predates 1980. If your inspection surfaces issues that require repair negotiations, your closing date can shift, which puts pressure on a tight lock period.
Appraisal availability varies by county. Rockingham, Hillsborough, and Merrimack counties tend to have faster appraisal turn times than Coos, Carroll, and Grafton. If you are buying in northern NH, build in extra lock cushion.
NHHFA programs have their own timelines. If you are using a New Hampshire Housing Finance Authority (NHHFA) Home Flex Plus loan or another NHHFA program, factor in the additional review steps when choosing your lock length.
Conforming loan limits. For 2026, the FHFA baseline conforming loan limit applies across all NH counties, which means there are no high-cost area exceptions in the state. Loans above the conforming limit are jumbo loans, which often have different lock structures.
Property taxes and your closing timeline
NH has no state income tax but some of the highest property taxes in the country. Your escrow setup at closing depends on when town tax bills are issued and paid. A delayed tax certificate from a town clerk can push your closing date and threaten your lock. Ask your loan officer to confirm the tax cycle for your specific town early in the process.
For buyers running the numbers, our mortgage calculators can help you see how a rate change of even 0.25% affects your monthly payment and total interest.
How NextGen Mortgage Loans Can Help
NextGen Mortgage Loans is a New Hampshire mortgage broker, not a single bank. That structure matters when you are deciding when and how long to lock a rate. We compare pricing across multiple wholesale lenders, so you can see how lock periods, float down options, and extension policies differ before you commit to one path.
We work with first-time buyers, move-up buyers, refinancers, veterans, and self-employed borrowers across every NH county. Our team can walk you through your loan estimate, explain exactly what your rate lock covers, and help you build a realistic closing timeline so your lock does not expire on the wrong day.
There is no cost or obligation to talk through your scenario. Get pre-approved with NextGen or run your numbers with our mortgage calculators before you commit to a lock.
Frequently Asked Questions About Mortgage Rate Locks
Can I lock a mortgage rate without a property under contract?
Some lenders offer pre-approval rate locks before you have a signed purchase agreement, but most require a property address. Without a contract, your timeline is uncertain, which makes lock management risky. Most NH buyers should wait until they are under contract.
Does a mortgage rate lock guarantee my loan approval?
No. A rate lock guarantees pricing on a specific loan scenario, but final approval still depends on underwriting, appraisal, title, and your continued financial qualification. If your credit, income, or the property changes, the lock can be repriced or voided.
How long can you lock a mortgage rate for new construction?
Lenders offer extended locks of 120 to 360 days for new construction in most cases. These locks usually carry pricing premiums and may require a non-refundable deposit. The exact options vary by lender, which is one reason new construction buyers benefit from working with a broker.
Can I switch lenders after locking my rate?
Yes. A rate lock is not a binding commitment to close with that lender. You can switch up until closing, although you will lose any application or appraisal fees already paid and start the process over. The new lender will issue a fresh lock at current market pricing.
What happens to my rate lock if rates drop significantly?
You generally stay locked at your higher rate unless your agreement includes a float down option or your lender offers a one-time renegotiation policy. Float down terms vary, so check your lock confirmation in writing.
Is the cost of a rate lock tax deductible?
Discount points paid to lower your rate may be deductible on a primary residence purchase loan in the year you pay them, subject to IRS rules. Lock extension fees and most other lock-related costs are generally not deductible. Consult a tax professional for advice specific to your situation.
When should NH buyers lock during the homebuying process?
Most NH buyers lock once they have a fully ratified purchase agreement, an inspection completed, and a clear path to closing within 30 to 45 days. If your transaction has complications such as a difficult appraisal county, a long inspection contingency, or NHHFA program review, a 60 day lock gives you a safer window.
