Have a 3 Percent Mortgage? Here’s What I’d Do First

Half the mortgages in this country are still under 4%. Credit card balances just hit $1.26 trillion at average rates over 22%. Both numbers are true, and a lot of the time it’s the same household carrying both. If you own a home in Santa Clara County with a 3 percent mortgage, you probably think it’s one of the best financial moves you ever made. It might be. But I keep hearing “I can’t move, I have a 3% rate” and “I can’t touch the house, I have a 3% rate.” Somewhere along the way the rate stopped being a tool and became an excuse.

I’m third-generation South Bay. I grew up in Almaden, went to Leland High School, and my family was here before this was Silicon Valley. I’ve watched a lot of owners here sit on a low rate while it quietly costs them money everywhere around the mortgage. Here are three owners, three different answers, and the math behind each one, as of November 2026.

I walked through all three examples on camera, with the numbers on screen.

What is your blended rate, and why does it matter with a 3 percent mortgage?

Your blended rate is the one number that tells you whether to ever touch a low-rate loan. Take every dollar of interest you pay in a year and divide it by every dollar you owe. That’s it.

Here’s owner one. You bought in 2021 with a $1 million loan at 3%. Your principal and interest payment is about $4,200 a month, and you owe about $875,000 today. Like a lot of people, you also carry $25,000 on credit cards and a $60,000 car loan.

Debt	Balance	Rate	Interest per year
Mortgage	$875,000	3%	About $26,000
Credit cards	$25,000	About 22%	About $5,500
Car loan	$60,000	A little over 7%	About $4,300
Total	$960,000	Blended: about 3.75%	About $36,000

Card rate from the Federal Reserve G.19 report for accounts that carry a balance. I used the Fed’s 22.15% figure on camera, as of November 2026. Rates on cards move quarter to quarter.

Lesson one: don’t refinance the mortgage

A cash-out refinance runs a little over 7% as of November 2026. Your blended rate is 3.75%. Every dollar you move from 3.75% to 7% is a loss, and you reset the clock to 30 years. I ran it. Rolling everything into one $965,000 loan at 7% is about $6,400 a month. Your three payments today add up to about $6,000. You’d pay more every month just to feel simpler. That’s a bad trade.

Lesson two: put out the fire in one room

Here’s the part people miss. That $25,000 on the cards is only about 2.5% of what you owe, but it costs $5,500 a year in interest. That’s a fire in one room of the house. You don’t rebuild the house. You put out the fire.

The average home equity line of credit was about 7.16% as of November 2026. Say you open a $25,000 line against the house, pay off the cards, and keep paying the same $600 a month.

$25,000 at $600 a month	Months to pay off	Total paid
Credit card at about 22%	About 81	About $48,000
Home equity line at about 7.16%	About 49	About $28,800
Difference	About 32 months sooner	About $19,000 saved

That’s around $19,000 for a phone call, and the 3% mortgage stays untouched. The rate was never the problem. One honest caveat: this owner only has $25,000 on cards. Plenty of people in the Bay Area carry a lot more, plus student loans. If your number is much bigger, a different structure might make sense. Run your own blended rate before anyone tells you what to do. I covered the other side of this, buying when rates are high, in what I’d do buying a home at 7 percent.

Can you move after 55 and keep your old property tax bill?

This is where I think the 3% rate story costs people the most, and it isn’t about the mortgage at all. Say you bought in Almaden in 1995 for $400,000. It’s worth about $2.2 million now. The stairs get harder every year, and you’d love a single-story home in Morgan Hill. Every time it comes up, someone says, “You’ll lose your 3%, and your property taxes will triple.”

The tax part is what stops people. Under Prop 13, your assessed value only rises about 2% a year. So you’re taxed on roughly $740,000, which is about $8,900 a year. Buy a $1.8 million house and you’d normally be assessed at $1.8 million, about $21,600 a year. So yes, roughly triple. I understand why people stay.

How Prop 19 changes the math

Since April 2021, Proposition 19 lets homeowners 55 or older carry their old assessed value to a replacement home anywhere in California, up to three times in their lifetime. You sell the Almaden house, buy in Morgan Hill within two years, and your new tax bill is based on your 1995 number, not your 2026 purchase price. The State Board of Equalization’s Prop 19 page lays out the rules.

There’s a catch, and I want to be accurate. If the new home costs more than the one you sold, the difference gets added on. Sell for $2.2 million and buy for $1.8 million and you carry the whole $740,000 assessment over. Sell for $1.8 million and buy for $2.2 million and about $400,000 gets added on top. That’s still far better than starting over at $2.2 million, but it isn’t free. The BOE also allows a little room on the price: a replacement bought in the first year after the sale can cost up to 105% of what you sold for, and up to 110% in the second year, before that adjustment kicks in.

Almaden owner since 1995, buying a $1.8M home	Assessed value	Approx. tax per year
Stay put (Prop 13 base)	About $740,000	About $8,900
Move without Prop 19	$1,800,000	About $21,600
Move with Prop 19	About $740,000	About $8,900
Savings with Prop 19		About $12,700 a year, $127,000 over 10 years

Tax estimates use roughly 1.2% of assessed value. Your actual rate depends on local bonds and assessments.

That’s $127,000 over 10 years to leave on the table because someone at a barbecue told you you’d pay triple. And on a house owned since 1995, the balance is probably small or gone. The 3% was never what kept you there. The tax bill was, and the tax bill moves with you now. If you’re weighing a smaller home, I also wrote about downsizing without debt, linked below.

What nobody puts on the balance sheet

I’ve lived the other side of this. Before real estate, I was a video producer at Tesla, and for years I commuted from Gilroy to Fremont. If you know, you know. I got in between 9 and 10 in the morning and left around 7 at night just to dodge the worst of it. It took a toll.

No one puts a commute on the balance sheet. Nobody lists the stairs, a 40-minute drive each way, or the bedroom nobody has used since 2019. Those are real costs. They just don’t show up as a rate. So when someone tells me they’re staying in the wrong house to protect a 3% rate, I think about 101 at 5 p.m. There’s a cost to staying too.

Need a bigger house but locked into 3 percent?

For owner three, the trap is real, and I won’t sugarcoat it. You bought a $1.5 million house in 2021. You owe $875,000 at 3% and pay about $4,200 a month. You’ve outgrown it. Maybe you work from home now, maybe you just need more space. You want the $2.2 million house.

Sell and buy, as of November 2026	Estimate
Net from selling at $1.5M (after loan payoff and costs)	About $530,000
New loan on a $2.2M home	About $1.67M at 7.2%
New principal and interest	A little over $11,000 a month
Change from today’s $4,200	About $7,000 more a month

That’s the trap. But there are two ways out most people never run.

Way one: don’t sell, rent it

Your 3% payment is $4,200. Add taxes and insurance and call it about $5,600 all-in. If the house rents for $5,500 to $6,000 a month, which a lot of $1.5 million houses in this county do, it roughly carries itself. Now you own two properties, and someone else is paying down a 3% loan. The catch: you still need a down payment for the new house without the sale proceeds, so this only works if you have cash or equity elsewhere. If you do, it’s the move I’d look at first. You keep the rate. You just stop living in it.

Way two: sell, with your eyes open

San Jose is the most equity-rich metro in the country right now. About 59% of homes with a mortgage here have at least 50% equity, as of November 2026. A lot of owners have more than $530,000 to put down, and every extra $100,000 down cuts roughly $680 a month off that payment at 7.2%. Then make the move once, for the house you’ll be in for 10 years, so you don’t pay a rate over 7% twice. For the bigger picture on where prices are headed, see the five forces repricing Silicon Valley home values.

What I would not do is what most people do: stay in the wrong house five more years, tell everyone it’s the rate, and put the kitchen remodel on a card at 22%. That’s the version where a 3% rate actually makes you poorer.

What I’d do first with a 3 percent mortgage

• Run my blended rate this week. Every debt, every rate, one number. If it’s under today’s mortgage rate, and for most of you it will be, the mortgage never gets refinanced.
• Move card balances to a home equity line and pay them off on a schedule. Then stop adding to the cards.
• If I’m 55 or older and thinking about moving, I’d call the Santa Clara County Assessor’s Office about Prop 19 before I call anyone else, including me.
• If I need a bigger house, I’d run the rent-it-out numbers before I ever ran the sale numbers.

And I’d stop saying “I can’t, I have a 3% rate.” You can. It’s just a different math problem than the one you’ve been running in your head. Every one of these depends on one number I didn’t give you: what your house is worth today. Not the Zillow number. The real comps.

FAQ

Should I refinance a 3 percent mortgage to pay off credit cards?

Usually not. A cash-out refinance is a little over 7% as of November 2026, and it moves your whole balance to that rate and restarts 30 years. A home equity line on just the card balance keeps the 3% loan in place and still cuts the card interest by about two thirds.

How do I calculate my blended interest rate?

Add up the interest you pay in a year on every debt, then divide by the total you owe. In my example, about $36,000 of interest on $960,000 of debt is a blended rate of about 3.75%. If that’s below today’s mortgage rates, your low-rate loan is doing its job.

Is a HELOC a good way to pay off credit card debt?

It can be, if you stop adding to the cards. At about 7.16% versus about 22%, paying $600 a month clears $25,000 in about 49 months instead of 81 and saves roughly $19,000. Your house secures the line, so treat the payment as non-negotiable.

Does Prop 19 let me keep my property tax base if I move?

If you’re 55 or older, Prop 19 lets you transfer your assessed value to a replacement primary home anywhere in California, up to three times. You have to buy within two years of selling. If the new home costs more, the difference is added to your transferred value.

Can I rent out my house and keep my 3 percent mortgage?

Many owners do. Your loan stays in place, and if rent covers your all-in costs, the property roughly carries itself. Check your loan terms, insurance, and taxes first, and remember you’ll need a separate down payment for the next home.

How much does $100,000 extra down lower a payment at 7.2%?

About $680 a month on a 30-year loan. That’s why owners with more equity than they realize should run the sale numbers with their real balance, not a guess.

Keep reading

• Buying a Home at 7 Percent: buydowns, seller credits, and what I’d do on the buy side.
• Downsizing Without Debt: how owners buy their next home with equity.
• Will There Be a San Jose Housing Crash?: what past downturns actually did to prices here.
• Should You Sell If You Relocate for Work?: the keep-or-sell decision when a job moves you.

Numbers in this post are examples and estimates as of November 2026, from my video and from the Federal Reserve. Rates change weekly. Check current rates with a lender, for example against Freddie Mac’s weekly survey. This is general information, not legal or tax advice. Talk with a tax professional and the Santa Clara County Assessor’s Office about your situation.