Most borrowers think of a rate lock as all-or-nothing: you lock your entire loan amount at a single rate, or you float and hope rates improve. A partial rate lock splits the difference, letting you lock part of your principal while leaving the rest floating. It's a niche feature that addresses specific timing problems, but it comes with administrative overhead and limited availability.
How a partial rate lock works
Instead of locking the full loan amount on day one, you lock a portion—say half—and leave the remainder unlocked. When you're ready to close or when a construction draw is funded, you lock the outstanding balance at the then-current rate. Your final note rate is the weighted average of the two locked portions. If you locked 200,000 at 6.25 percent and later locked another 200,000 at 6.75 percent, your blended rate would be 6.50 percent on the full 400,000. These figures are illustrative; rates and products are subject to change and this is not a commitment to lend.
The feature is designed for scenarios where your funding needs arrive in stages: construction-to-permanent loans with multiple draws, land-and-build packages, or purchases where the seller demands a long closing window and you want some rate protection early. Locking incrementally spreads your rate risk across time rather than concentrating it at a single moment.
Who offers partial locks and why they're rare
Partial rate locks are uncommon because they multiply underwriting and hedging complexity. The lender must track two or more lock periods, expiration dates, and extension fees on a single file. Secondary-market investors who buy loans prefer uniform, easily pooled products; a loan with a blended rate from multiple locks is harder to sell. Most wholesale and correspondent channels don't support the feature at all, so even brokers with diverse lender panels rarely encounter it.
A handful of portfolio lenders and large construction specialists offer partial locks, typically on jumbo or one-time-close construction loans. Expect strict eligibility requirements: the lender may require the full loan amount to be locked before the final draw, charge separate lock-extension fees for each segment, and limit how many partial locks you can take. The feature is a risk-management tool, not a rate-speculation device—lenders won't let you cherry-pick favorable rate windows indefinitely.
The Alliance take: weigh the overhead against the benefit
Partial locks solve a real problem if you're building and worry that rates will spike between the foundation pour and the roof. But the administrative cost is real. You'll coordinate multiple lock confirmations, track overlapping expiration dates, and potentially pay multiple extension fees if the project runs long. For straightforward purchases or refinances with predictable closing dates, a standard single lock is simpler and cheaper. If your scenario genuinely benefits from phased locking, confirm in writing that your lender supports it, understand the fee structure for each segment, and document every lock date and amount. Construction timelines slip; make sure your partial-lock strategy includes buffer time and a plan for extensions.
Ready to explore your lock options? Start an application and we'll walk through the timing that fits your project.