Locking a rate
By Samprit Biswas, editor · Updated October 8, 2026
A rate lock is a lender's promise to hold a rate, and its points, for a set number of days while your loan is made. Rates move every day; with a lock, yours does not.
When to lock
A buyer usually locks once they have a signed purchase contract and have chosen a lender; a homeowner refinancing, when they apply. Lock early and you need a longer lock; wait, and the rate may move first, in either direction.
How long, and what it costs
A lock runs for a set number of days, chosen to cover the time to closing. A longer lock usually costs more, as a slightly higher rate or a fee, because the lender carries the risk for longer. If the lock runs out before closing, extending it usually costs extra, so ask how long your lender's closings take.
If rates fall after you lock
Some lenders offer a float-down: a chance to take a lower rate if rates drop enough before closing, usually for a fee. Ask before you lock: it is usually part of the lock itself.
Our estimates are not a lock
No lender is bound by our numbers. They show which way rates are moving, and an alert can tell you when today's estimate reaches the rate you want, so you know when to call lenders.
How to cite this page
InfinityRateWatch. "Locking a rate." https://infinityratewatch.com/learn/locking-a-rate/. Data as of Oct 8, 2026.