Rate Lock

A rate lock is a commitment made by a lender to a borrower, guaranteeing a specific interest rate, and often associated fees or points, for a defined period of time while a mortgage application is being processed toward closing. Without a rate lock, the interest rate on a mortgage application can continue to float with the broader market right up until closing, meaning a borrower could end up paying a different rate than initially quoted if market rates move in the meantime.

Rate locks typically last somewhere between thirty and sixty days, though shorter and longer periods are available depending on the lender and the loan program, often at different cost. Locking in too short a period risks the lock expiring before closing actually occurs, which can force the borrower to pay for an extension or accept a new, potentially higher, rate.

A rate lock works like reserving today's price on a big purchase, even though the item will not actually be delivered for several weeks. Mortgage rates can move daily based on broader financial market conditions, and a rate lock removes that uncertainty for the borrower, guaranteeing the rate quoted now will still apply once the loan actually closes, provided it happens within the locked period.

Because lenders bear the risk that rates might move against them during a locked period, rate locks are sometimes offered free for a standard length of time, with a fee charged for longer locks or for extending a lock that is about to expire before closing.

• The specific interest rate guaranteed for the stated lock period.
• Any points or lender fees associated with that rate.
• The length of the lock period, after which the guarantee expires unless extended.

If closing is delayed beyond the locked period, a borrower may need to pay a fee to extend the lock, or accept a new rate based on current market conditions at the time of closing, which could be higher or lower than the originally locked rate.

Some lenders offer a float-down option alongside a rate lock, allowing a borrower to take advantage of a lower rate if market rates fall significantly after locking, rather than being stuck with the originally locked, now comparatively higher, rate. This feature typically comes at an additional cost, either as an upfront fee or built into a slightly higher locked rate, and borrowers weighing whether to pay for it are essentially deciding how much they are willing to pay for the flexibility to benefit if rates move favourably during the lock period.

Without a float-down option, a standard rate lock works in only one direction: it protects the borrower if rates rise, but does not pass along any benefit if rates happen to fall before closing, unless the borrower is willing to let the original lock expire and start the process again.

Many lenders offer a standard rate lock period, often around thirty to forty-five days, free of any explicit charge, built into the overall cost of originating the loan, while charging an additional fee only for longer lock periods or for extending a lock that is close to expiring. Borrowers applying for a mortgage during a period of fast-closing transactions may be comfortable with a shorter, free lock, while those anticipating delays, such as a complex property purchase or a slower closing process, may choose to pay for a longer lock from the outset to avoid the risk and cost of needing an extension later.

Comparing the specific lock periods and any associated fees offered by different lenders is a useful, though sometimes overlooked, part of evaluating competing mortgage offers, particularly for borrowers anticipating a longer or less certain path to closing.

Some rate locks include a built-in tolerance allowing the lender a small amount of flexibility near the end of the lock period without formally extending it, recognising that a closing can sometimes slip by just a day or two for routine administrative reasons unrelated to the borrower's own actions.