An 80-10-10 mortgage is a financing arrangement in which a homebuyer uses two simultaneous loans plus a cash down payment to reach 100% of a home’s purchase price. The breakdown is:
– First mortgage: 80% of the home’s value (loan-to-value, or LTV, = 80%).
– Second mortgage: 10% of the home’s value (a second lien, often a home equity line of credit or HELOC).
– Cash down payment: 10% of the home’s value.
This structure is a form of a “piggyback” mortgage (a second loan taken at the same time as the primary mortgage). It’s commonly used to avoid private mortgage insurance (PMI), which lenders typically require when a buyer’s down payment is less than 20% of the purchase price. PMI protects the lender if the borrower defaults and raises the buyer’s monthly housing cost.
Key terms (short definitions)
– Loan-to-value (LTV): The ratio of a loan amount to the value or purchase price of the property. Lender risk rises as LTV increases.
– Private mortgage insurance (PMI): Insurance paid by the borrower to protect the lender on loans with LTVs above a lender’s threshold (usually 80%).
– Piggyback mortgage: A second loan originated at the same time as the first mortgage to reduce the primary loan’s LTV.
– Fixed-rate mortgage: A mortgage whose interest rate remains the same for the life of the loan.
– Adjustable-rate mortgage (ARM): A mortgage with an interest rate that can change periodically, typically tied to an index.
– HELOC (home equity line of credit): A revolving credit line secured by the home; interest is charged only on the amount drawn.
How it typically works
– The first loan (80% LTV) is usually a conventional fixed-rate mortgage.
– The second loan (10% LTV) is often an adjustable-rate instrument such as a HELOC or a second mortgage. Because it’s secured by the home, its interest rate is normally lower than unsecured credit but higher than the first mortgage.
– Combining the two loans lets the buyer put only 10% cash down while keeping the first mortgage at 80% LTV, which usually removes the requirement for PMI.
Why buyers use it (benefits)
– Avoid or delay PMI: By keeping the primary mortgage at 80% LTV, many lenders won’t require PMI, lowering monthly payments compared with a single 90% loan that carries PMI.
– Potentially lower rate on the main mortgage: First-mortgage interest rates may be lower than for a single larger mortgage with higher LTV.
– Flexibility: A HELOC can function like a reusable line of credit once established.
Main risks and trade-offs
– Higher cost on the second loan: HELOCs and second mortgages commonly carry higher interest rates than first mortgages, which reduces some of the savings from avoiding PMI.
– Variable payments: If the second loan is an ARM or HELOC, its rate (and monthly payment) can rise over time.
– Greater downside if prices fall: In a declining market you’re more likely to have low or negative home equity, increasing the risk of being “underwater” (owing more than the home is worth).
– Complexity and closing costs: Two loans may mean two sets of closing fees and separate terms to manage.
When an 80-10-10 might make sense
– You have ~10% available for a down payment but not 20%.
– You want to avoid PMI for monthly-payment or cost reasons.
– You expect to pay down the second loan quickly (e.g., sell another property, use savings), or you plan to refinance later.
– You accept the variable-rate risk on the second lien or can obtain a fixed-rate second loan.
Step-by-step checklist for evaluating an 80-10-10 loan
1. Confirm current cash available for down payment and closing costs.
2. Get rate quotes and APRs for: first mortgage (80% loan), second mortgage/HELOC (10%), and for a single 90% conventional mortgage (including PMI).
3. Compare total monthly payment and total first-year costs (mortgage payment + interest + PMI or HELOC interest + fees).
4. Check second-loan terms: fixed vs. variable rate, interest-only options, draw period, repayment schedule, and prepayment penalties.
5. Ask about closing costs for both loans and whether any fees duplicate.
6. Consider your time horizon: how long you expect to hold the home and whether you can pay down or refinance the second loan.
7. Stress-test the plan: what happens to monthly payments if the HELOC rate increases or home prices fall?
8. Verify lender policies on removing PMI if you later reach 20% equity.
Worked numeric example (illustrative)
Scenario: Purchase price = $300,000. Buyer has $30,000 cash (10%).
Option A — single conventional loan (90% LTV):
– Mortgage amount: $270,000 (90% of $300,000).
– Buyer would likely pay PMI because LTV > 80%.
Option B — 80-10-10 structure:
– First mortgage (80%): $240,000.
– Second mortgage / HELOC (10%): $30,000.
– Cash down: $30,000.
Comparison notes:
– With Option B the primary mortgage is at 80% LTV, generally avoiding PMI.
– The buyer must pay interest on the $30,000 second loan; that rate is commonly higher than the first mortgage but lower than typical credit-card rates.
– If the buyer expects to eliminate the second loan soon (for example, by selling another property or refinancing), Option B can lower monthly expenses relative to carrying PMI on a 90% single loan.
Practical questions to ask lenders
– What are the interest rates and APRs for both loans and for a comparable single 90% mortgage with PMI?
– Is the second loan a fixed-rate second mortgage or an adjustable-rate HELOC? What are the index and margin?
– Are there interest-only periods, and how long are they?
– What are the closing costs and fees for each loan?
– How, and under what conditions, can I eliminate PMI in the future if I choose the single-loan route?
Sources for further reading
– Investopedia — 80-10-10 Mortgage:
– Consumer Financial Protection Bureau (CFPB) — What is private mortgage insurance?: /
– CFPB — Home equity lines of credit (HELOCs): /
– U.S. Department of Housing and Urban Development (HUD) — Buying a home resources
Educational disclaimer
This explainer is for general informational and educational purposes only. It is not personalized financial, legal, or tax advice. For decisions about mortgages or home financing, consult a qualified mortgage professional, attorney, or financial advisor who understands your specific circumstances.