What is a rate lock?

You've finally find that home, the seller has accepted your offer, and you've gotten a contract. Congratulations!

It's time for you to lock in your rate. Or at least decide if you should.

When you lock your rate, your lender is basically saying: “We’ll honor this interest rate even if the market changes.”

Most locks are good for 30-60 days, sometimes longer if you're building a home.

Why lock? Because rates can jump unexpectedly. A rate lock gives you some peace of mind. You can budget around a predictable payment, even if rates spike next week.

This allows you to get your financing in order with a predictable payment and closing costs.

Floating vs locking

If you don’t lock, your rate is “floating,” which means it moves with the market. This is riskier but can pay off if rates drop. You’re gambling. If they go up? You’re stuck paying more.

Floating might make sense if you think rates will drop and you’re not closing super soon. Otherwise, locking is usually the safer play.

Can I change my rate after I lock it?

Yes.

When you lock, you’re usually locking in a menu of options, or the rate table, not just one rate.

That menu (aka a “rate sheet”) includes higher rates with lender credits (help cover closing costs), and lower rates that cost more upfront (called points).

You can still switch between these choices later, you're not stuck with the exact rate you picked, as long as you stay on the same rate sheet.

Example:

• 6.375% = $2k lender credit (less cash at closing, higher monthly payment)
• 6.125% = you pay $6k in points (more cash now, lower monthly payment)

It’s all about trade-offs.

The key is to run the break-even math. If it takes you 5 years to save back the upfront cost in monthly payments and you’re moving in 3, then don’t bother with points.

Here's a break-even calculator for you.

You can usually pivot between different rates on the rate sheet you locked, but make sure you do it with advance notice. Maybe 2 weeks before at the latest.

What is a float-down?

A float-down is like a “just in case” clause. If you lock at 6.5% and the market drops to 6.0%, a float-down lets you grab the lower rate, usually one time.

It’s not always free.

Some lenders charge for it (flat fee or a small percent of the loan), and some only offer it if rates drop by a certain amount.

Ask your lender:

• Do you offer float-downs?
• How much does it cost?
• When can I use it?
• How far do rates need to drop?

Not all lenders offer this, so ask early.

What are my options if rates drop and I want to take advantage?

1. Float down (if the lender offers it)
2. Start over with a new lender. Risky. If you're with a broker, the broker will transfer your file. If you aren't, and choose to switch lenders, you’ll have to reapply. This is risky if you have tight deadlines.

#3 This isn’t a casual decision, it’s a last resort.

Consider working with a mortgage broker for situations like this. Since a broker represents several lenders, they'll have several options for you, and you won't have to exactly start fresh by yourself. They'd help you transfer your file.

Can I switch loan programs after locking?

Like switching from FHA to Conventional? Or 30-year to 15-year?

You’ll have to lock again based on current market rates.

So talk to your loan officer before making that move. It changes the whole loan, so it can affect your timeline, cost, and qualification.

Locking Tips (Don’t skip this part)

• Get everything in writing. Don’t rely on verbal promises. You should have a written lock confirmation and see it listed on your Loan Estimate.
• Ask about float-downs and extensions. What happens if you need more time? Is there a cost?
• Don’t mess with your credit or finances. No big purchases. No new credit cards. No job changes. Your lock assumes your financials stay the same.
• Be realistic about timing. Don’t try to time the market perfectly. If rates are trending up and you’re nervous, lock it. If rates seem stable and you’ve got time, maybe float a bit and watch.

What I tell people

Once we get to 2 weeks before closing, I tell buyers to put their blinders on. It's probably not worth the risk of breaking your contract because you heard rates dropped 0.25%

Two weeks out, keep your eye on the prize (the house).

Exception: The loan officer should keep an eye on rates. If it's a week out and there's a chance for a float-down, I'd take that one. Just not changing or transferring lenders.

Real-world story: When rates kept dropping

I had clients who locked in a solid rate. Then rates fell. Good news, they had a float-down and used it.

Then rates fell again. Their lender didn’t offer a second float-down, so we switched lenders mid-process. Risky, but the savings were worth it.

Then rates dropped again. The new lender let them float-down again.

End result: multiple float-downs, new lender, huge savings. Not typical, but a good reminder, understanding your options matters.

Final thought

Rate locks aren’t just paperwork. They’re a strategy. Know your lender’s rules, ask smart questions, and make sure you’re locking in flexibility, not just a number.