Your closing window
The lock should extend beyond the expected closing date with enough room for ordinary processing or scheduling delays.
Mortgage rate-lock decision
Should I lock my mortgage rate today?
A rate lock is less a prediction about tomorrow and more a decision about which risk you can live with today. Compare the lock period, closing date, extension terms, and payment impact before choosing to lock or float.
The direct answer
Lock when the available offer works for your budget and the lock is long enough to cover a reasonably reliable closing date.
Waiting may help if rates fall, but it can also raise your payment or change the points and lender credits attached to the rate. There is no universally correct day to lock. The better question is whether the possible benefit of waiting is worth the pricing risk you are keeping.
Four facts to confirm
Do not lock a headline rate. Lock a complete offer.
The complete price
Confirm the interest rate, APR, points, lender credits, lender-controlled fees, and lock period together. A rate without its price is incomplete.
The extension policy
Ask what happens if the lock expires, how an extension is priced, and who pays when the delay is not yours.
The float-down terms
If rates fall after locking, ask whether the lender offers a float-down, what market movement triggers it, and what it costs.
Worked example
A quarter-point move is a budget decision, not just a market headline.
Illustrative assumptions: $400,000 loan, 30-year fixed mortgage, principal and interest only, no change in points, lender credits, fees, loan program, or borrower qualifications. Actual pricing can move by more or less, and changes in points or credits can matter as much as the rate.
Possible rateMonthly P&IDifference from 6.50%
6.25%$2,462.87$65.40 less per month
6.50%$2,528.27Starting offer
6.75%$2,594.39$66.12 more per month
This example isolates principal and interest to show rate sensitivity. It excludes taxes, insurance, mortgage insurance, closing costs, points, lender credits, and changes in loan balance. It is educational math, not a rate quote or market forecast.
Lock or float?
Let your circumstances decide which risk matters more.
Your situationWhat may deserve more weightWhy
You are under contract with a firm closing dateA lock that safely reaches closing.A payment increase or expired lock can create more disruption than the possibility of a modest market improvement.
You have more time and meaningful budget flexibilityThe lender's float and float-down choices.You may be able to tolerate market movement, but you should define the rate or payment that would cause you to lock.
Your closing date is uncertainLock length and extension policy.A short lock can look cheaper until a delay creates an extension charge or repricing risk.
The lender changed the scenario after quotingA revised apples-to-apples comparison.A different loan amount, program, credit profile, appraisal, or down payment can change pricing even after a lock.
Questions worth asking
Get these answers in writing before you lock.
Exactly when does the lock expire?
Confirm the date, time, time zone, and whether the loan is reasonably expected to close before then.
What is locked?
Confirm the rate, points, lender credits, and other rate-dependent terms shown on the revised Loan Estimate.
What can still change?
Ask how a changed appraisal, credit score, income finding, loan amount, down payment, or loan program would affect the lock.
What happens if rates fall or closing is delayed?
Ask for the float-down and extension policies, including thresholds, fees, and responsibility for lender-caused delays.
Use your scenario
Compare the offer before deciding whether to protect it.
Lenny can compare matched rates, payments, upfront lender costs, and timeline costs without reducing the decision to a rate forecast.
Quick answers
Questions borrowers ask before locking
Should I lock my mortgage rate today?
Consider locking when you have a mortgage offer you would accept, a reasonably reliable closing date, and a lock period long enough to reach closing. Floating may preserve the benefit of a market decline, but it also leaves your rate, payment, points, and lender credits exposed to market movement.
How long should my mortgage rate lock be?
The lock should comfortably cover the time from locking through closing. Compare the price of available lock periods, the expiration date, the lender's extension policy, and who pays if closing is delayed.
Can my mortgage rate change after I lock it?
A lock generally protects the quoted rate through its expiration if the loan closes on time and the application does not materially change. Changes to the loan amount, program, down payment, credit, income, appraisal, or other application facts can still change pricing.
What happens if mortgage rates fall after I lock?
Your original lock may remain in place unless the lender offers a float-down or renegotiation option. Ask before locking whether a lower market rate can be captured, what threshold applies, and whether there is a fee.
Official sources
Know what a rate lock does and does not protect.
- CFPB: What is a lock-in or rate lock?
- CFPB: Choose a loan offer and review the lock period
- CFPB Regulation Z: Loan Estimate rate-lock disclosure
- Freddie Mac: Why consider a rate lock-in
Reviewed August 17, 2026 by Gregg Harris, Mortgage Loan Originator (NMLS 205617). Educational guidance only. A licensed mortgage lender must confirm lock availability, duration, pricing, conditions, extension terms, and final disclosures.