Rate Locks Explained: Lock Periods, Extensions and Float-Downs

You found the house. Your offer was accepted. Now your loan officer asks a question that sounds simple but can be worth thousands of dollars over the life of your loan: "Do you want to lock your rate?"

A mortgage rate lock is one of the most useful tools a buyer has, and one of the least understood. Pick the wrong lock period and you could pay for time you don't need, or watch your lock expire a few days before closing. This guide walks through how rate locks work, how to choose a lock period, what happens when you need an extension, and when a float-down option is worth asking about.

What is a mortgage rate lock?

A rate lock is your lender's commitment to hold a specific interest rate for you for a set period while your loan moves toward closing. In the words of the Consumer Financial Protection Bureau, a lock means "your interest rate won't change between the offer and closing," as long as you close within the lock period and nothing material in your application changes.

Why does that matter? Because mortgage rates move constantly, sometimes daily. Freddie Mac's weekly Primary Mortgage Market Survey showed the average 30-year fixed rate at 7.32% for the week of October 22, 2026, down from 7.40% just one week earlier. Moves like that, in either direction, change your monthly payment. A lock takes that uncertainty off the table while you finish the process.

How to tell if your rate is actually locked

Don't assume. Check your Loan Estimate. Federal rules require the top of page 1 to include a "Rate Lock" line that states whether your rate is locked. If it is, the form has to show the exact date and time (including time zone) the lock expires. If it isn't, the form notes that your rate, points and lender credits can still change.

If that line says "No," your rate is still floating, no matter what anyone has told you on the phone. Ask for written confirmation once you lock.

Choosing a rate lock period

According to the CFPB, rate locks are typically offered for 30, 45 or 60 days, and sometimes longer. The right choice comes down to one question: how long until you realistically close?

As a general rule, the longer the lock, the more it costs. That cost might show up as a slightly higher rate, a fee, or fewer lender credits. A short lock is the least expensive, but it only helps you if you actually close inside it.

Here's a practical way to think about it:

• 30 days can work for a refinance or a straightforward purchase where the appraisal, title and paperwork are already moving.
• 45 days gives you breathing room for a typical purchase, especially if the appraisal or the seller's side might slow things down.
• 60 days or longer makes sense for transactions with more moving parts, such as co-op purchases that need board approval, new construction, or deals with a long contract-to-close timeline.

In Westchester, timing is often shaped by things outside your control: attorney review, title work, condo or co-op paperwork, and appraisal scheduling. Build in a cushion. A lock that is a week too long usually costs less than a lock that runs out three days early.

What can still change a locked rate?

A lock protects you from market movement, not from changes in your own file. The CFPB lists several situations where a locked rate can still change:

• You switch loan types or change your down payment
• The appraisal comes in higher or lower than expected
• Your credit score changes, for example because you opened a new loan or missed a payment
• Your lender can't document income such as overtime or bonuses

The takeaway: once you lock, keep your financial life boring. Don't finance a car, open new credit cards or change jobs without talking to your loan officer first. (If you're still preparing, this guide on building a strong mortgage application covers what underwriters look for.)

Rate lock extensions: what happens if closing is delayed

Closings slip. Appraisals come back late, a title issue surfaces, a seller needs more time. If your lock is about to expire before you can close, you'll usually have two choices:

1. Extend the lock. Most lenders will extend for a fee or a rate adjustment. The CFPB warns that extensions "may be expensive," and your Loan Estimate won't tell you what an extension costs, so ask about this upfront.
2. Let it expire and relock. If rates have risen since you locked, relocking could mean a higher rate. If they've fallen, the lender's relock policy will decide whether you benefit.

Before you lock, ask your loan officer three questions:

• What does an extension cost, per day or per week?
• Who pays if the delay is caused by the lender?
• What happens if I need to relock?

Knowing the answers in advance turns a stressful surprise into a planned decision.

What is a float-down option?

The biggest worry buyers have about locking is simple: "What if rates drop after I lock?" That's where a float-down comes in.

A float-down option lets you take advantage of a lower rate if the market improves after you've locked. Not every lender offers one, and the terms vary widely. Common conditions include:

• Rates must fall by a minimum amount before the float-down can be used
• It can usually be exercised only once
• It may come with an upfront cost or a slightly higher starting rate
• It must be used within a certain window before closing

Whether a float-down is worth it depends on how much it costs, how volatile rates are, and how long your lock period is. On a long lock in a choppy market, it can be valuable peace of mind. On a short, simple refinance, it may not be worth paying for.

Locking vs. floating: how to decide

Floating means you wait to lock, hoping rates improve. Sometimes that works out, and sometimes it doesn't. No one can reliably predict short-term rate moves, and that includes economists, lenders and loan officers.

A few honest guidelines:

• Lock if the current rate gives you a payment you're comfortable with, if your budget is tight, or if you'd lose sleep watching the market.
• Consider floating only if you have real flexibility in your budget and timeline, and you've accepted that rates could rise.
• Remember the alternatives. A lock isn't the only way to manage your rate. Discount points and buydowns can also lower your payment. This breakdown of how rate buydowns work in 2026 explains how buyers and sellers are using them.

How rate locks fit into the bigger picture

A rate lock is one step in a longer process: pre-approval, house hunting, contract, application, underwriting, appraisal and closing. Timing your lock well means knowing where you are in that sequence. If you're new to buying, my complete guide to getting a mortgage lays out each stage, so you can see where the lock fits. The CFPB's Your Home Loan Toolkit is also a solid free resource for comparing offers.

Frequently asked questions

How long does a mortgage rate lock last? Most rate locks last 30, 45 or 60 days, and longer locks are sometimes available. Longer locks generally cost more.

Does it cost money to lock a mortgage rate? It depends on the lender and the lock length. The cost may be built into your rate or charged as a fee, and longer locks usually cost more. Ask your lender how the cost changes with the lock period.

Can my rate change after I lock? Yes, if your application changes. Changing your loan type or down payment, an unexpected appraisal value, a credit score change or income that can't be documented can all affect a locked rate.

What happens if my rate lock expires before closing? You will usually need to extend the lock, often for a fee, or relock at current market rates, which could be higher or lower than your original rate.

What is a float-down on a mortgage? A float-down is an optional feature that lets you lower your locked rate if market rates drop by a set amount before closing. Not all lenders offer it, and the terms and costs vary.

When is the best time to lock a mortgage rate? Most borrowers lock once they have an accepted offer and a realistic closing date, choosing a lock period long enough to cover that timeline with some cushion.

Talk through your rate lock strategy

Every transaction has its own timeline, and the right lock depends on yours. If you're buying or refinancing in Westchester County and want a clear plan for when to lock, how long to lock and what to do if closing moves, reach out to me directly. I'm happy to walk you through your options before you commit.

Disclaimer: The information provided in this blog is for general informational and educational purposes only and should not be considered financial, legal, tax, or professional advice. Every individual's circumstances are different, and readers should consult qualified professionals before making decisions based on the information presented. While we strive to ensure accuracy and keep the content up to date, no guarantee is made that all information is complete, current, or applicable to every situation. Any examples are illustrative and should not be interpreted as a guarantee of results. The views expressed are for informational purposes and do not necessarily represent the views of any affiliated organization. Readers are encouraged to independently verify relevant information before acting on it.