Mortgage Rate Lock Strategy: When to Lock and How to Protect Your Rate

Your mortgage rate is not guaranteed until you lock it. From application to closing — typically 30 to 45 days — rates move every business day based on bond market conditions, economic data, and global events. Managing this risk requires a clear rate lock strategy.

What a Rate Lock Is

A rate lock is a commitment from your lender to honor a specific interest rate and points for a defined period — typically 30, 45, or 60 days. If rates rise during the lock period, your rate is protected. If rates fall, you typically stay at the locked rate unless your lock has a float-down provision.

Lock Periods and Cost

Longer locks cost more. A 30-day lock is typically the base price. A 45-day lock adds a small premium. A 60-day lock adds more. Extended locks of 90 to 180 days for new construction carry meaningful rate premiums — sometimes 0.5% or more.

The Float-Down Option

Some lenders offer a float-down provision — you lock your rate now but retain the right to capture a lower rate once during the lock period if rates improve by a defined threshold. This costs slightly more than a standard lock but provides both protection and upside. Valuable when rates are elevated and you believe they may improve before closing.

When to Lock

In a rising rate environment: lock as early as possible — the risk of waiting outweighs the potential upside. In a falling rate environment: a shorter lock or a float-down provision gives you exposure to improvements. In a stable environment: lock when you find the rate and program you are comfortable with — monitoring the market adds anxiety for minimal potential benefit in stable conditions.

Rate Lock Extensions

If closing is delayed beyond your lock expiration, extensions are available — typically for a fee calculated as a percentage of the loan amount per additional week or month. Factor potential extension costs into your financing budget, especially on new construction or transactions with complex title situations.

At East Coast Mortgage, we advise every borrower on rate lock strategy based on current market conditions. Book a call to discuss timing and lock structure for your transaction.