Rate Lock, Explained: How Long It Lasts, What It Costs, and When It Expires
Published 2026-11-08 · eLoanTree Blog
Mortgage rates move every day. Between the day you apply for a loan and the day you close, the rate you were quoted can rise — and a higher rate means a higher monthly payment for years.
A rate lock is the tool that stops that movement, for a set period, while your loan closes. It is simple in concept and full of fine print in practice: what it covers, how long it lasts, what it costs, and what happens if your closing slips past the deadline.
Key Takeaways
- A rate lock is a lender’s agreement to hold a specific interest rate — and usually the associated discount points — for a defined period while the loan is processed.
- The protection is conditional: it holds only if you close within the agreed time frame and there are no changes to your application, such as the loan amount, down payment, loan type, or credit profile.
- Rate locks typically run 30, 45, or 60 days, according to the CFPB; shorter locks of about 7 days and longer locks up to 120 days also exist.
- A standard 30- to 60-day lock may cost roughly 0.25% to 0.50% of the loan amount when charged explicitly — on a $400,000 loan, 0.25% is $1,000 — and longer locks cost more.
- If a lock expires before closing, the rate floats back to the current market rate; a float-down, where offered, lets you move to a lower rate once, usually only if rates have fallen by around a quarter of a percentage point.
- Lock when the payment at today’s rate works for your budget and your closing date is covered with a cushion of a week or two — and always get the lock, its expiration date, and the extension terms in writing.
1. What a rate lock is
A rate lock, or lock-in, is a lender's agreement to hold a specific interest rate — and usually the associated discount points — for a defined period while your loan is processed. The CFPB describes it this way: if your rate is locked, it will not change between the time you get the lock and your closing date, as long as you close within the agreed time frame and there are no changes to your application.
Two parts of that definition matter. First, a lock freezes the rate and the points together, not just the rate. If you locked a rate with one discount point, that combination is what is held. Second, the protection is conditional.
It holds only if you close on time and only if your application stays the same. Change the loan amount, the down payment, the loan type, or your credit profile in a meaningful way, and the lender can revisit the rate.
Get the lock in writing. The Loan Estimate must state whether your rate is locked and, if so, the exact date and time — including the time zone — when the lock expires. If your rate is not locked, you are floating: the rate on the Loan Estimate is a snapshot, and it can shift by the time you close.
2. How long a lock lasts
Rate locks typically run 30, 45, or 60 days, according to the CFPB, and sometimes longer. Shorter locks of about 7 days and longer locks up to 120 days also exist, according to the Federal Reserve's consumer guide to rate locks, but 30 to 60 days covers most standard purchases.
The right length depends on your closing timeline. A 30-day lock is the cheapest, but it carries a real risk: if underwriting, the appraisal, or the seller's side runs slow, the lock can expire before you sign.
A 60-day lock costs more but removes that pressure. A good rule is to choose a lock period that covers your expected closing date with a cushion of a week or two, not one that ends on the exact day you hope to close. Hope is not a closing strategy.
Source: Consumer Financial Protection Bureau (CFPB), as cited in the article
3. What a lock costs
A lock is not always billed as a separate line item. Many lenders build the cost of the lock into the rate they offer, so there is no separate invoice — you pay for it as a slightly higher rate. When lenders do charge an explicit fee, it is usually quoted as a percentage of the loan amount, and longer locks cost more, because the lender takes on more risk for a longer time and must hedge that risk in the market.
As a general pattern, a standard 30- to 60-day lock may cost roughly 0.25% to 0.50% of the loan amount when charged explicitly, with longer locks costing more; exact fees vary by lender, market conditions, and loan type, and some lenders charge no separate fee at all.
On a $400,000 loan, 0.25% is $1,000. That is the price of certainty for two months. Whether it is worth it depends on what a rate rise would cost you — and a rise does not have to be large to matter.
As a hypothetical illustration, on a $400,000 30-year fixed loan, a 0.25-point rise in the rate adds roughly $66 a month to principal and interest, or about $23,800 more interest over the full term if the loan is kept that long. That is the cost of floating into a higher rate, and it is why many buyers lock once the payment at today's rate works for their budget.
4. When a lock expires
If your closing is delayed and the lock expires before you sign, your rate floats back to the current market rate. If rates have risen, your new rate will be higher, and your monthly payment will be higher. If rates have fallen, you may get a lower rate — but you cannot count on that, and the lender is not obligated to give you the old rate back.
5. Float-down: the one-way door
A float-down is an optional provision some lenders offer. It lets you lock a rate but still move to a lower rate if the market improves before closing — usually only once, and usually only if rates have fallen by a minimum amount, often around a quarter of a percentage point. The lender sets the trigger, and not every lender offers a float-down at all.
6. Should you lock or float?
There is no rule that works every time, because nobody knows where rates will go next. But there are two questions that make the decision clearer. First: does the payment at today's rate work for your budget? If yes, locking protects a payment you can already live with.
If no, you should not be counting on rates to fall to make the loan affordable — that is a gamble, not a plan. Second: how close is your closing, and how certain is the timeline? The closer and more certain the closing, the less a lock costs you in risk. The further away and the more moving parts there are, the more a longer lock is worth.
7. The bottom line
A rate lock freezes your rate and points for 30, 45, or 60 days — sometimes longer — while your loan closes, as long as you close on time and your application does not change. Longer locks cost more. If the lock expires, you re-lock at the market rate or pay for an extension.
A float-down can let you capture a lower rate after locking, but it costs extra and only pays off if rates fall enough and you keep the loan long enough. Lock when the payment at today's rate works and your closing date is covered with room to spare. And always get the lock, its expiration date, and the extension terms in writing.
Sources: Consumer Financial Protection Bureau, "What's a lock-in or a rate lock on a mortgage?"; Federal Reserve consumer guide to mortgage rate locks; CFPB Regulation Z, Loan Estimate rate-lock disclosure. The $400,000 payment illustration is a hypothetical example, not a quote.
Educational only — eLoanTree is not a lender or broker and does not make loan decisions, guarantee rates or approval, or collect documents or SSNs.
Sources & further reading
Every figure in this article is dated and sourced in the text above. These official sources were used — open them to check the current figures: