Purchase · 5 min read
What happens if mortgage rates jump after I am pre-approved but before I lock?
September 23, 2026 · Updated September 24, 2026 · Written by Bill Egan, NMLS 7342
Short answer
A pre-approval is not a rate lock. A lock is the lender holding a specific interest rate for a set number of days. If rates jump before you lock, the payment on the same house can be higher than the number on your letter. Lock when you have a contract, and ask what the new payment is before you write the offer.
01
Why this comes up
You got a pre-approval letter with a payment that fit the house. Then mortgage rates moved higher in a single morning, before you had a signed contract and before anyone locked a rate. You want to know if the letter is still real, and whether you just lost the house because the monthly number changed.
02
Where this goes wrong
The offer goes in using yesterday’s payment. The seller accepts. When the loan is locked, the principal and interest is higher than the letter, and the payment no longer fits the budget you and your agent used. Earnest money is already in. The seller will not cut the price, and you do not have a clean way out if the contract does not give you one. Or you freeze and do not write the offer at all, while someone else who already locked, or who can live with the new payment, gets the house.
03
What we do about it
Rates can move by the hour on some days, so a payment from last week, or even from this morning, may not be the payment you would have this afternoon. Watch the rates page for the daily trend, then talk with your loan officer before you write the offer so you are using a current number. We will rerun the payment with you. The pre-approval still does not hold the rate. Once you have a contract, we lock for enough days to finish the loan.
04
How to get ready
Ask for the payment at today’s rate before you write an offer, not the payment from last week’s letter. If that number is too high, lower the price you will pay or the loan amount. Do not stretch the house to keep yesterday’s payment. When the contract is signed, ask how many days the lock lasts and what it costs if closing runs past that date. Keep the pre-approval current so the seller’s agent can still call and confirm it.