Combine your first and second mortgage or HELOC — see your blended rate, total monthly payment, and whether refinancing saves money.
🏠 First MortgagePrimary
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🏠 Second Mortgage / HELOCSecondary
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📈 Compare to Single Refinance
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Enter current market refinance rate
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Typical: 2%–5% of new loan
📈 Blended Rate Analysis
Blended Rate
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Weighted average
Combined Monthly
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Both mortgages
Total Loan Balance
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First + second
First Mortgage
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monthly
Second Mortgage
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monthly
Refi Monthly
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single new loan
🔴 Current — Two Mortgages
1st mortgage rate—
2nd mortgage rate—
Blended rate—
Combined payment—
Total interest (remaining)—
🟢 Refinanced — Single Loan
New rate—
New loan balance—
Closing costs—
Monthly payment—
Total interest—
Loan balance distribution
■ 1st: 80%■ 2nd: 20%
Enter your mortgage details above and click Calculate.
What is a Blended Mortgage Rate?
A blended mortgage rate is the weighted average interest rate across your first mortgage and any second mortgage or HELOC. Because each loan has a different balance and rate, the blended rate reflects the true average cost of your combined mortgage debt.
Piggyback loans (80/10/10) — a first mortgage at 80% LTV + a second at 10% to avoid PMI.
HELOC + primary mortgage — home equity line of credit alongside your main mortgage.
Refinancing decision — is the new refinance rate lower than your blended rate?
Debt strategy planning — should you pay off the second mortgage first?
Rate comparison — understanding your true all-in borrowing cost.
Should You Refinance to a Single Mortgage?
Refinancing into a single loan makes sense when the new rate is meaningfully lower than your blended rate, AND you plan to stay in the home long enough to recoup closing costs. Use the breakeven formula: Monthly Savings ÷ Closing Costs = Breakeven Months. If you'll stay longer than the breakeven period, refinancing typically makes sense.
Second Mortgage Types
Home Equity Loan
Fixed-rate, lump-sum second mortgage. Monthly payments are predictable. Good for large one-time expenses. Rates typically 1%–3% higher than primary mortgage rates.
HELOC (Home Equity Line of Credit)
Variable-rate revolving line of credit. Rate tied to Prime Rate + margin. Flexible draw period (usually 10 years) followed by a repayment period. Rates fluctuate with market conditions.
Piggyback / 80-10-10 Loans
Common structure: 80% first mortgage + 10% second mortgage + 10% down payment, avoiding PMI. The second loan typically carries a higher rate and shorter term than the first.
Frequently Asked Questions
A blended mortgage rate is the weighted average interest rate across your first mortgage and any second mortgage or HELOC, calculated by weighting each loan's rate by its balance relative to the total. It represents the true combined cost of your mortgage debt.
It depends on the rates involved. If your second mortgage rate is significantly higher than your first, aggressively paying it down reduces your blended rate faster. If both can be refinanced into a single loan at a lower blended rate, refinancing may be better — use this calculator to compare.
Compare the new refinance rate to your current blended rate. If the refi rate is lower, calculate the monthly savings and divide by closing costs to find the breakeven period. If you plan to stay in the home longer than the breakeven period, refinancing typically saves money.
An 80-10-10 loan uses a first mortgage for 80% of the home price, a second mortgage for 10%, and a 10% down payment — avoiding PMI. The second loan typically carries a higher rate. This calculator helps you see the blended rate across both loans.
Yes — you can refinance the second mortgage independently without touching the first. This is called a standalone second mortgage refinance. However, the lender of the first mortgage usually must consent. Refinancing only the second may make sense if the first has a great rate you want to keep.
A HELOC adds variable-rate debt on top of your fixed first mortgage. As HELOC rates rise (they track the Prime Rate), your blended rate increases. Enter your current HELOC rate in this calculator to see your true combined rate and whether consolidation makes sense.
