When to Lock In Your Mortgage Rate Before Closing

Should you lock your mortgage rate this week, or wait and hope it comes back down? If you have an accepted offer and a closing date 30 to 45 days out, the sources lean toward locking now, for a period that ends a few days after your closing date. A rate lock is your lender's written promise to hold your interest rate and points until a set date, as long as you close by then and nothing in your application changes.

This week's number is why the question feels urgent. Freddie Mac's Primary Mortgage Market Survey put the 30-year fixed at 7.28% on October 1, 2026, up from 7.03% a week earlier. That is a 25 basis point move. A basis point is one hundredth of a percentage point. The jump followed a September in which the weekly average climbed from 6.71% to 7.03%. Until you lock, you are floating, which means your rate moves with the market every day.

The CFPB's definition is narrow. A lock keeps your rate, and usually your points, fixed between the loan offer and closing. It holds only if you close inside the lock period and your application details stay the same. The written lock agreement should state four things: the rate, the points, the length of the lock and any fees. The CFPB's advice is to get all of it in writing before you rely on a quote.

Length is where the money is. According to RealCostReport's lock cost guide, a 30-day lock is typically free. On a $400,000 loan, a 45-day lock costs $0 to $500, a 60-day lock costs $500 to $1,000, and a 90-day lock costs $1,500 to $2,000. The price does not rise evenly. Going from 30 to 45 days is nearly free, and the cost climbs from there.

To size the lock, start with how long the steps take. The same guide cites ICE Mortgage Technology data showing purchase loans average 11 days from application to lock and 26 days from lock to closing. A 30-day lock therefore leaves a cushion of about four days on an average file. One late appraisal or one slow condition uses that up.

If the lock expires before you sign, you pay to extend it. Fees vary by source. AmeriSave's guide puts extensions at 0.125% to 0.500% of the loan amount per period, sold in 7-day or 15-day blocks. On a $400,000 loan that is $500 to $1,000 for seven days and $1,000 to $2,000 for fifteen. RealCostReport cites a wider range of 0.25% to 1% of principal. How lenders price and waive lock extension fees is the reason the lock length matters more than the rate you lock at.

A float-down is an add-on that lets your locked rate drop if market rates fall before closing. It is not automatic. The CFPB notes that some lenders require a minimum drop before you can use it, some allow it only once, and some allow it only in a set window before closing. The sources disagree on the price. The CFPB says 0.125% to 0.25% added to the rate or an upfront fee. AmeriSave says 0.125% to 0.25% of the loan amount, and RealCostReport says about 0.25%. Amortio quotes 0.25% to 1.0%. The usual trigger is a market drop of at least 0.25%, and some lenders require 0.50%. Without a float-down, AmeriSave says, getting a lower rate after you lock usually means a relock fee of 0.25% to 0.50% of the loan amount.

The weekly survey trailed the daily market. PMMS is a weekly average for conventional loans with 20% down and excellent credit. Mortgage News Daily, which tracks daily lender rate sheets, had the 30-year at 7.60% on September 30. Your loan officer locks off the daily sheet, not the Thursday headline.

The forecast missed. AmeriSave reports that six major forecasters expected the 30-year to fall from 6.66% on September 1 to between 6.20% and 6.40% by the fourth quarter. Rates crossed 7% three weeks later. A buyer who floated on that forecast lost the bet.

The case for a drop exists, but it is unproven. HousingWire's Logan Mohtashami points to the mortgage spread, which is the gap between the 10-year Treasury yield and mortgage rates. It reached 1.98% in late September, against a normal range of 1.60% to 1.80%. If the spread narrows, rates could fall even if Treasury yields do not. He also warns that 8% rates become plausible if the 10-year yield reaches 5.40%. It stood at 5.240% on September 29. No source says which will happen first. A run of falling Treasury yields would point one way, and a 10-year yield near 5.40% would point the other.

The 7.28% PMMS figure is a national average. It is not the rate you can lock. Your quote depends on your file, your loan type and that day's pricing.

A lock is also not a guarantee that holds no matter what. Under the CFPB's definition, it holds only if your application details stay the same. If your income, loan amount or credit changes, the lender can reprice your loan.

Amortio's guide recommends locking as soon as the contract is accepted for most buyers. It suggests floating only during consecutive declines in Treasury yields or after weak inflation data, and September produced neither. Count from today to your contract closing date, add a buffer, and pick the lock length that covers it. Remember that the last stretch, from clear to close to signing, has its own waiting period, so the buffer has to cover it.