The short version
Take what the refinance actually costs you. Divide it by what you save each month. That's your break-even in months. If you're confident you'll keep the loan well past that number, refinancing makes sense. If you're not, it doesn't.
That's it. There is no magic rate drop. A quarter-point on an $800,000 jumbo can pencil out. A full point on a $180,000 balance often doesn't.
Two things wreck this math more than anything else: counting money that isn't really a cost, and quietly restarting a 30-year clock you were seven years into paying down.
How do you actually calculate the break-even point?
Let me use a real-shaped example. Say you owe about $585,000 at 7.25%, with roughly 27 years left. Principal and interest runs around $4,095 a month. You can refinance into a new 30-year at 6.5%, and the lender fees, title, escrow, appraisal, and recording come to about $9,500.
The new payment is roughly $3,698. You're saving about $398 a month. Divide $9,500 by $398 and you get about 24 months. Two years to break even. If you plan to stay past that, this is a clear yes.
Rates and fee structures move constantly, so treat these figures as illustrative. Run yours on your actual balance, your actual quote, and your actual closing costs.
One more layer people skip: compare against staying put and doing nothing. Sometimes the answer is that you make an extra principal payment instead and skip the whole transaction.
- Costs that count: lender fees, title and escrow, appraisal, recording, credit report, any points you buy.
- Costs that don't: the new impound account. You're funding it, but you get your old one refunded within a few weeks.
- Prepaid interest is close to a wash. You skip a payment month on the way out, so most of it comes back to you in cash flow.
- Savings should be measured on principal and interest only. Don't credit the refinance for a lower payment that's really just a tax bill that moved.
Why is the 1% rule bad advice?
Because it ignores loan size entirely, and loan size is doing most of the work.
On a $900,000 balance in Healdsburg, a quarter-point drop is worth well over $100 a month. With a lender credit covering most of the fees, that can break even in under a year. Meanwhile, a full-point drop on a $150,000 balance might save $90 a month against $6,000 in costs, and that's five and a half years of waiting to get back to even. Same rate movement, completely different answers.
I've also seen the rule used as an excuse to sit still. Someone bought at the top of the rate cycle, waited for the full point that never quite arrived, and passed on a three-quarter-point drop that would have paid for itself in 18 months. The rate never came back. Run your own numbers instead of a rule of thumb.
What does restarting the 30-year clock really cost?
This is the part that gets buried. If you're three years into a 30-year loan and you refinance into a brand-new 30, your payment drops partly because of the lower rate and partly because you just stretched the remaining balance back out over 360 months.
In the example above, that lower payment comes with 33 more years of payments than the 27 you had left. You can still come out ahead, but not by as much as the monthly savings suggests.
The fix is simple and almost nobody asks for it. Keep making the old payment. On that same $585,000 at 6.5%, paying $4,095 instead of the required $3,698 wipes out the loan in about 23 years instead of 27. Lower rate, shorter payoff, and you never feel a change in your budget.
Or ask for a shorter term outright. A 25-year or 20-year fixed often prices close to the 30, and it locks the discipline in for you.
Does a no-cost refinance actually exist?
Sort of. Nothing is free. What's happening is that the lender pays your closing costs with a credit, and you take a slightly higher rate in exchange. That's a legitimate trade, not a trick, as long as you understand it.
It's usually the right structure in two situations. First, when you think rates may keep sliding and you'd refinance again within a couple of years. Paying $9,500 twice is a bad plan. Second, when your break-even on the paid-cost version is uncomfortably long.
It's the wrong structure when you're settling into a forever home. If you're confident you'll hold this loan for eight or ten years, taking the lower rate and paying the costs almost always wins.
Ask your loan officer to show you both side by side, with the monthly payment and the break-even on each. If someone won't put that in front of you, that tells you something.
- No-cost: higher rate, zero out of pocket, best for short holds or a likely second refinance.
- Costs paid: lowest rate, break-even math applies, best for long holds.
- Rolling costs into the balance is a third option. You still paid them. They're just financed, and they still belong in your break-even calculation.
Will refinancing reset my property taxes in California?
No, and this comes up constantly in Sonoma County. Under Proposition 13, your assessed value only resets on a change of ownership or new construction. A refinance is neither. Your appraisal is for the lender's eyes, not the Assessor's.
So if you bought in Santa Rosa in 2012 and your assessed value is far below what the house is worth today, refinancing does not touch that. You keep your basis.
What refinancing can affect locally is the rest of your housing payment. If your impound account was built on an old insurance premium and your carrier just repriced you after a fire-zone review, the new escrow analysis will reflect that higher number. That's not the refinance's fault, but it's why some people refinance into a lower rate and see their total payment barely move. Know which line item is doing what before you sign.
When should you not refinance?
Some files just don't work, and a good loan officer will tell you so early.
If you're planning to sell or relocate inside your break-even window, skip it. If you're within a few years of paying the thing off, the interest savings on a small remaining balance rarely justify the cost. If you've got a 3% pandemic-era rate and you're only refinancing to consolidate a modest credit card balance, look hard at whether a second mortgage or a HELOC keeps that first-lien rate intact instead.
And if you're refinancing to pull cash out and your reason is a want rather than a need, sleep on it. Turning a 20-year problem into a 30-year problem is easy to do and hard to undo.
- Moving within two to three years, and the break-even is longer than that.
- Under roughly five years left on the loan.
- Sitting on a rate in the 2s or 3s that you'd be trading away for cash.
- Credit or income changed for the worse since you closed, which can mean pricing that erases the benefit.