Her Float-Down Fee Could Be $750 or $3,000 on the Same $300,000 Loan. Only One of Those Numbers Pays for Itself.

7 min read · Last updated August 24, 2026

Key takeaways:

A float-down typically costs 0.25% to 1% of your loan amount, and the low and high ends of that range are not close: $750 versus $3,000 on a $300,000 loan.
Most lenders require the market rate to drop at least 0.25 percentage points before you can exercise the option, and you usually have to use it 5 to 15 days before closing.
At the cheapest fee tier, a float-down breaks even in about 15 months. At the most expensive tier, it takes just over five years, longer than most owners hold their first rate before refinancing or moving.
Navy Federal lets borrowers re-lock a rate twice for free within a 60-day window. A shorter initial lock plus a free re-lock can beat paying for a float-down you may never need.

Maria locked her rate at 6.67% on a $300,000 mortgage three weeks ago, then watched Freddie Mac’s weekly survey slip to 6.65% the next week. Her loan officer offered her a float-down: pay a fee now, and if the market drops enough before closing, she gets to swap into the lower rate. The quote came back at $1,500, half a point of her loan balance, due before she even knew whether the drop would be big enough to use it.

A float-down is a private contract term, not a federal protection. The Consumer Financial Protection Bureau defines a rate lock but has no page on float-downs at all, so every number below is lender-specific until you get it in writing.

What a float-down actually buys you

A rate lock freezes your interest rate between your loan offer and closing, as long as you close inside the agreed window and nothing changes on your application. The Consumer Financial Protection Bureau (CFPB), the federal agency that regulates mortgage disclosures, confirms locks typically run 30, 45, or 60 days. A float-down is a separate, optional add-on some lenders sell on top of that lock: pay a fee, and if rates fall far enough before you close, you get to move to the lower one instead of staying stuck at your locked rate.

The fee itself is not standardized, and sources genuinely disagree on the shape of the range. CBS News quotes a mortgage professional describing fees running “from a quarter point to more than one full point of the loan amount,” an open-ended top end, not a hard ceiling. AmeriSave’s own glossary states a narrower 0.25% to 1% of loan amount range, which works out to $750 to $3,000 on a $300,000 loan. A separate AmeriSave article narrows that further to 0.125% to 0.50% for some programs, while Embrace Home Loans charges a flat quarter point with no range at all. Chase and Lower.com decline to publish a number entirely, telling borrowers pricing is fully lender-specific. Treat 0.25% to 1% as the commonly quoted range, not a guarantee of what your own lender charges or a true ceiling on the fee.

The trigger is more consistent. Most lenders require the market rate to fall by at least 0.25 percentage points before you’re allowed to exercise the option, though some set the bar at 0.375% or 0.50%, and a few cap your total benefit at 1.00% even if rates fall further. You typically have to invoke it 5 to 15 days before closing, sometimes inside a window that only opens partway through your lock and closes again before the finish line.

The breakeven math on a $300,000 loan

Here’s what that actually costs and saves on a loan locked at this week’s rate. Freddie Mac’s Primary Mortgage Market Survey (PMMS) put the 30-year fixed rate at 6.67% the week Maria locked. A float-down that clears the typical 0.25-point minimum trigger would move her to 6.42%.

Loan amount	Payment at 6.67%	Payment at 6.42%	Monthly savings	Fee at 0.25%	Breakeven	Fee at 1.00%	Breakeven
$300,000	$1,929.87	$1,880.45	$49.42	$750	15.2 months	$3,000	60.7 months
$400,000	$2,573.16	$2,507.26	$65.89	$1,000	15.2 months	$4,000	60.7 months

Breakeven math on a 30-year fixed loan locked at 6.67% (Freddie Mac PMMS, week of August 13, 2026), floated down to 6.42% at the typical 0.25-point minimum trigger. Fee and savings both scale with loan size, so the breakeven timeline is the same at $300,000 and $400,000.

That last column is the real takeaway. The fee and the savings both scale with your loan balance, so the breakeven timeline depends only on which fee tier your lender quotes, not on loan size. At the cheapest tier, a float-down pays for itself in about 15 months. At the most expensive tier, it takes just over five years, longer than most homeowners hold a first mortgage rate before refinancing or selling. Ask which end of that range you’re actually being quoted before you agree to pay.

The catch: lenders can split the difference

A float-down agreement sets the fee and the trigger before you sign, not after.

Some float-down products don’t reprice you to the actual market rate. One lender’s own explainer describes repricing instead to the market rate plus a margin, commonly an eighth of a point, and frames the logic this way: lenders wouldn’t split the difference if rates rose against you, so some build the same asymmetry into a float-down, giving you most of the drop but not all of it.

Ask your lender exactly what rate you land on if you exercise it. Some float-downs reprice to the market rate plus an eighth of a point, not to the market rate itself, which quietly shrinks the savings side of the breakeven math above.

There’s no regulator setting a floor on this. The CFPB’s own guidance stops at defining the rate lock and never mentions float-downs at all, because this entire product is a private agreement between you and your lender, which is exactly why getting the exact numbers in writing matters. If you’re weighing whether a float-down is worth it, compare it against locking your rate in the first place and against rate buydowns and discount points, which solve a related but different problem.

The alternative: a shorter lock and a free re-lock

A float-down isn’t the only way to hedge against a rate drop. Lock length itself is priced, and The Mortgage Reports publishes one worked example of how that pricing works: a 7-day lock quoted 25 basis points below the same lender’s 30-day rate, and a 60-day lock quoted 25 basis points above it, a 50-basis-point spread from shortest to longest. A shorter lock means less protection if your closing slips, but it also costs less up front than paying for a float-down you may not need.

If your timeline changes, some lenders let you re-lock instead of extend. Bankrate found real fees ranging from a flat charge to a percentage of the loan: Guild Mortgage charges $1,500 for a 120-day lock, Pennymac charges a flat $595 for a 60, 75, or 90-day lock, and Navy Federal offers a 60-day lock with two free re-locks in that window. If you’re comfortable re-shopping instead of paying for a guaranteed option, that combination can beat a float-down fee outright, especially at the expensive end of the range. The same logic applies if your closing gets delayed and your lock is about to expire, and getting a second quote before you lock anything is usually the cheapest move of all.

Disclaimer: This article is for informational purposes only and is not financial, legal, or tax advice. Rates, fees, and lender terms change frequently. Consult a licensed mortgage professional for guidance specific to your loan.

Frequently asked questions

What is a mortgage rate float-down option? It’s a paid add-on to a rate lock. You pay a fee upfront, and if the market rate drops enough before closing, usually by at least a quarter point, you get to switch into the lower rate instead of staying locked at your original one.

How much does a float-down usually cost? Published figures run from 0.25% to 1% of your loan amount, or $750 to $3,000 on a $300,000 loan. Some lenders charge a flat quarter point instead of a range. Ask for your exact fee before locking.

How much does the rate have to drop before I can use it? Most lenders require at least a 0.25 percentage point drop, though some set the bar at 0.375% or 0.50% and cap your total benefit at 1.00%. You typically have 5 to 15 days before closing to exercise it.

Is a float-down ever a bad deal? It can be, mainly at the high end of the fee range. A 1% fee takes just over five years to break even, which is longer than many owners keep their first rate. A 0.25% fee breaks even in about 15 months, which is a much easier case to justify.

What should I ask my lender before paying for one? Get the exact fee, the exact trigger in percentage points, the exercise deadline, and whether the payoff reprices to the full market rate or to market rate plus a margin. All four numbers change whether it’s worth paying for.