Refinance or Keep Your Low Rate? How a Blended Rate Tells You

If you locked in a mortgage rate under 4% a few years ago, you've probably caught yourself thinking, "I'm never giving this rate up." I get it. I hear some version of that from clients nearly every week.

Today's rates are a lot higher. Mortgage News Daily put the 30-year conventional rate at about 7.50% on October 8, 2026, and Bankrate's national average for a 30-year fixed refinance was 7.64% on October 10, 2026.

Life keeps going, though. You might want to renovate, pay off expensive debt, cover tuition, or (if you're an investor) pull equity out for your next deal. That leaves two main options:

1. A cash-out refinance, which replaces your current mortgage with one bigger loan at today's rate.

2. Keeping your first mortgage and adding a second lien, such as a HELOC or a home equity loan.

A second-lien rate is almost always higher than a first-mortgage rate, so the second option can look worse at first glance. The way to get a real answer is to calculate your blended rate.

What Is a Blended Rate?

A blended rate is the weighted average interest rate across all the loans on your property, with each loan weighted by its balance. Here's the formula:

Blended Rate = (B1 × r1 + B2 × r2) ÷ (B1 + B2)

Where:

• B1 = balance of your first mortgage

• r1 = interest rate on your first mortgage

• B2 = balance of your second lien (HELOC or home equity loan)

• r2 = interest rate on your second lien

Your low-rate first mortgage is usually much bigger than the second lien, so it does most of the work in the average. A high rate on a small balance doesn't move the blend as much as people expect.

A Worked Example (Hypothetical)

All numbers below are hypothetical and for illustration only. They are not a quote or an offer.

Say you owe $300,000 at 3.5% on your first mortgage, with 25 years left. You want $60,000 in cash.

Option A: Keep the first and add a second lien

• Hypothetical home equity loan: $60,000 at 9.0%, 15-year fixed

Blended rate = ($300,000 × 3.5% + $60,000 × 9.0%) ÷ $360,000 = ($10,500 + $5,400) ÷ $360,000 = about 4.42%

Option B: Cash-out refinance

• Hypothetical new loan: $360,000 at 7.5%, 30-year fixed

Your effective rate on the whole $360,000 is now 7.5%.

On rate alone it isn't close: 4.42% blended vs. 7.5%. Rate isn't everything, though, so let's look at the payments and the total interest.

• Option A (keep + second lien): first mortgage ~$1,502/mo (25 yrs left) + second lien ~$609/mo (15 yrs) = ~$2,110/mo; total interest if held to term ~$200,100

• Option B (cash-out refi): ~$2,517/mo; total interest if held to term ~$546,200

In this example, keeping the low rate saves roughly $407 a month, and far less interest is paid over the life of the loans. Part of that interest gap comes from the refi starting a fresh 30-year clock, which is one more reason to compare full loan scenarios instead of just headline rates. (I checked these figures with a standard amortization calculation. They cover principal and interest only and leave out taxes, insurance, and closing costs.)

Important Caveats

The blended rate is a starting point, not the whole answer. Keep these in mind:

• Second liens often have shorter terms. A 10- or 15-year home equity loan can mean a higher payment on that piece even when the blended rate is lower.

• Many HELOCs are variable. The rate you start with may not be the rate you have in two years. Model a few "what if rates rise?" scenarios.

• HELOCs often have draw and repayment periods. Interest-only payments during the draw period can look cheap until repayment begins and the payment jumps.

• Fees matter on both sides. Compare closing costs, appraisal fees, and any annual or early-closure fees.

So run three comparisons: blended rate, monthly payment, and total interest over the time you actually expect to keep the loans.

When a Refinance Wins Instead

Keeping a low rate isn't always the right call. A refinance can come out ahead when:

• Your current rate is above today's rates. If your existing mortgage carries a higher rate than what you could get now, keeping it doesn't protect anything.

• You can remove PMI. If your home has gained enough value, a refinance might eliminate private mortgage insurance, and that can be a meaningful monthly savings.

• You're consolidating high-interest debt. If you carry credit card or other high-rate balances, rolling them into a mortgage may lower your overall cost. Do this carefully, because it turns unsecured debt into debt secured by your home.

• You want to move from an ARM to a fixed rate. If your adjustable rate is about to reset, the predictability of a fixed rate can be worth a lot.

• Your second-lien options are poor. If the only HELOC or home equity loan offers available to you carry very high rates or tight terms, the blended rate may not come out ahead.

Don't Forget the Break-Even

For any refinance meant to lower your payment, calculate the break-even point:

Break-even (months) = Closing costs ÷ Monthly savings

Hypothetical example: If a refinance costs $6,000 in closing costs and saves you $250 per month, your break-even is $6,000 ÷ $250 = 24 months. If you plan to stay in the home (or keep the loan) longer than two years, the refi may make sense. If you might sell or refinance again sooner, it probably doesn't.

The Investor Angle: Pulling Equity for Your Next Deal

For BiggerPockets investors, this question comes up all the time, whether you're funding a down payment on the next rental or running the refinance step of a BRRRR.

A few things to think about:

• Keep cheap debt where you can. If a rental already carries a sub-4% first mortgage, a second lien may let you tap equity without repricing the whole balance at today's rates.

• A HELOC can be flexible capital. Some investors use a HELOC like a revolving line for down payments or rehab costs, then pay it down after the next refinance or sale. Just remember the variable-rate risk.

• BRRRR math has changed. At today's rates, the "refinance" in BRRRR can squeeze cash flow. Stress-test your rent against the new payment before you count on pulling all your capital back out.

• Investment property guidelines differ. Second-lien availability, loan-to-value limits, and pricing are often different for investment properties than for primary residences.

Calculate the blended rate on every property and every scenario. It's one of the simplest ways to compare options side by side.

Let's Run Your Numbers

Every situation is different. Your balance, your rate, your goals, and how long you plan to hold the property all change the answer. If you're weighing a cash-out refinance against a HELOC or home equity loan, I'm happy to run your actual numbers through a blended rate calculator with you and walk through payments, total interest, and break-even. No pressure, just a clear picture so you can decide what's right for you.

Feel free to reach out to me here on BiggerPockets anytime.

— Randi Orzoff

Randi Orzoff, NMLS #2058648. Barrett Financial LLC, NMLS #181106. Randi is also a licensed real estate agent in Georgia and Nevada. This article is for educational purposes only and is not a commitment to lend. All rates, terms, and programs are subject to change without notice and subject to borrower qualification, underwriting, and property eligibility. All examples are hypothetical and for illustration only; they are not quotes or offers of credit. Rate figures cited are from Mortgage News Daily (October 8, 2026) and Bankrate (October 10, 2026) and may have changed. Consult a tax advisor regarding your specific situation. Equal Housing Opportunity.