10 min read · Last updated September 28, 2026
- On a $450,000 home with 10 percent down, an 80-10-10 piggyback loan can run about $280 less per month than a single loan carrying private mortgage insurance (PMI), at rates available the week of September 24, 2026.
- Federal law, the Homeowners Protection Act of 1998 (HPA), forces automatic PMI termination once your balance reaches 78 percent of your home’s original value. You can request cancellation earlier, at 80 percent, but no similar law forces a second lien to disappear.
- The Consumer Financial Protection Bureau (CFPB) warns that a piggyback second lien often carries a higher, frequently adjustable rate, so today’s savings can shrink or reverse if rates move against you.
- Refinancing your first mortgage while a second lien is in place typically requires a resubordination agreement under Fannie Mae’s own Selling Guide, an extra step a single PMI loan never requires.
An 80-10-10 piggyback loan splits a home purchase into an 80 percent first mortgage, a 10 percent second lien, and a 10 percent down payment, letting a buyer skip private mortgage insurance entirely. On a $450,000 home at current rates, that structure can cost about $280 less per month than a single loan with PMI, but the second lien never cancels itself the way PMI does by law.
In this article
- What an 80-10-10 piggyback loan actually is
- The monthly math: a piggyback loan against PMI
- The moment PMI cancels itself, and the lien that never does
- What the second lien costs you at refinance or sale
- The verdict: when the piggyback is the smart play
- Frequently asked questions
Priya Nair put $45,000 down on a $450,000 house outside Charlotte, North Carolina, and her loan officer laid out two ways to cover the rest. One path added a $253 monthly bill for private mortgage insurance (PMI) to her loan, for years. The other split her financing into two separate loans and skipped that bill from the day she closed.
What an 80-10-10 piggyback loan actually is
An 80-10-10 loan is not one loan. It is two, closing on the same day. The first mortgage covers 80 percent of the purchase price. A second loan, either a home equity line of credit (HELOC) or a fixed-rate second mortgage, covers another 10 percent. The buyer’s own cash covers the last 10 percent. Combined, the two loans reach the same 90 percent of the purchase price a single loan would reach, but neither loan alone crosses the 80 percent line that normally triggers PMI.
The Consumer Financial Protection Bureau (CFPB) describes this exact split as its own textbook example: a 10 percent down payment, an 80 percent main mortgage, and a 10 percent “piggyback” second mortgage. The agency is blunt about the second lien’s price tag, noting it “typically carries a higher interest rate, which is also often adjustable.” A 5 percent down payment works the same way at a different split, commonly called 80-15-5: an 80 percent first mortgage, a 15 percent second lien, and 5 percent down.
The CFPB also notes this structure was common during the mortgage boom of the early-to-mid 2000s and is rarer today, though lenders still offer versions of it under different brand names. PMI prices off the whole loan. A second lien prices off only the slice that would otherwise trigger it.
The monthly math: a piggyback loan against PMI
| Factor | Single Loan With PMI | 80-10-10 Piggyback Loan |
|---|---|---|
| How it works | One first mortgage, plus a monthly PMI premium added to the payment | Two loans closing together: an 80% first mortgage and a 10% second lien, no PMI |
| Rate on the smaller share | Same rate as the first mortgage; PMI is a separate premium, not a rate | The second lien typically prices higher than the first mortgage, and is often adjustable |
| Monthly cost, $450,000 home, 10% down | $2,956 (see worked example below) | $2,675 (see worked example below) |
| How it ends | Ends automatically at 78% of original value, or earlier on request at 80%, under federal law | Does not end on its own; must be paid off, refinanced, or converted when the draw period ends |
| Your next refinance | Nothing extra to arrange once PMI is already cancelled | The second lien must be resubordinated or paid off before the new first mortgage can close |
| Best for | A buyer who wants the simplest paperwork and expects to stay long enough for PMI to cancel | A buyer comfortable managing a second loan who wants the lower payment starting now |
Here is the same choice with Priya’s real numbers. Her house costs $450,000. She has $45,000 for a 10 percent down payment either way, so the only question is how the remaining $405,000 gets financed.
Path one: a single loan plus PMI. Priya borrows $405,000 at 7.03 percent, the 30-year fixed rate Freddie Mac’s Primary Mortgage Market Survey reported for the week of September 24, 2026. Her loan payment (principal and interest) comes to $2,702.64 a month. Assume a PMI rate of 0.75 percent a year, in the lower half of the 0.46 percent to 1.50 percent range Bankrate’s own rate research cites from the Urban Institute’s Housing Finance Policy Center. That adds $253.12 a month ($405,000 x 0.0075 / 12). Her total: $2,955.76 a month.
Path two: an 80-10-10 piggyback. The first mortgage shrinks to $360,000 (80 percent of the price) at the same 7.03 percent, for a payment of $2,402.35. The second lien is a $45,000 HELOC priced at 7.28 percent, the national average Bankrate’s own survey of lenders reported on September 23, 2026, running interest-only during the draw period. That adds $273.00 a month ($45,000 x 0.0728 / 12). Her total: $2,675.35 a month.
The piggyback saves Priya $280 a month while PMI is active. But watch what happens next.
The moment PMI cancels itself, and the lien that never does
PMI is not permanent, and federal law says so. Under the Homeowners Protection Act of 1998, the CFPB confirms a servicer “must automatically terminate PMI” once your balance is scheduled to reach 78 percent of your home’s original value. That happens automatically as long as your payments are current. You also have “the right to ask your servicer to cancel PMI” earlier, once your balance is scheduled to fall to 80 percent of that original value.
Run Priya’s amortization schedule on the $405,000 loan and those thresholds land on real dates. Her balance hits 80 percent of the $450,000 original value ($360,000) around month 101, about 8 years and 5 months in, when she can request cancellation. It hits 78 percent ($351,000) around month 116, about 9 years and 8 months in, when termination becomes automatic even if she never asks. If she wants to force the appraisal-based path sooner, using a fresh valuation rather than waiting on the amortization schedule, PHW’s guide to forcing PMI removal through an appraisal walks through that math separately.
Nothing in federal law does the same thing for a second lien. Once Priya’s PMI cancels around year 8, her single-loan payment drops to $2,702.64, just $27.29 more than the piggyback’s now-permanent $2,675.35. But her piggyback’s $45,000 HELOC balance has not moved an inch if it ran interest-only. She still owes the full $45,000, while her single-loan balance has been amortizing the entire time.
What the second lien costs you at refinance or sale
A second lien follows the house, not the calendar. If Priya refinances her first mortgage while the HELOC is still open, Fannie Mae’s Selling Guide requires “execution and recordation of a resubordination agreement” whenever the second lien stays in place. The one exception is state law that lets a lien keep its existing position automatically, with no new paperwork. Otherwise it is an extra document, an extra signature from her second lender, and in some cases an extra fee, none of which a PMI-only loan ever requires.
The size of a new second lien is not unlimited, either. Fannie Mae calculates a combined loan-to-value (CLTV) ratio by adding the first mortgage, the drawn HELOC balance, and any other subordinate financing, then dividing by the lesser of the sale price or appraised value. The maximum CLTV a given loan type allows is published in Fannie Mae’s own Eligibility Matrix, and it varies by loan program. That is why a lender has to run this math before agreeing to add a second lien on top of a refinance, not just a purchase.
This same second-lien mechanic shows up in a different context too. A down payment assistance loan is also a second lien with its own subordination and payoff rules, just with a different purpose. If Priya’s gap were on the down payment itself rather than the loan structure, PHW’s breakdown of down payment assistance liens covers the three questions to ask before signing one.
The verdict: when the piggyback is the smart play
Take the piggyback if you plan to stay eight to ten years and can qualify comfortably for two loans instead of one. You want the lower payment starting now, not later. The monthly savings are real, and they show up in the first billing cycle.
Skip it if you expect to refinance within the next few years, or if you cannot say with confidence you would qualify for a second-lien loan on top of your first mortgage. A single loan with PMI is the simpler instrument. It costs more for a while, then it cancels itself by law and costs nothing more.
Frequently asked questions
What does “80-10-10” actually mean? It describes how a home purchase is financed: 80 percent by a first mortgage, 10 percent by a second lien (a HELOC or fixed second mortgage), and 10 percent by the buyer’s down payment. The two loans together cover the same amount a single 90 percent loan would, without triggering private mortgage insurance.
Is an 80-15-5 loan the same idea with less money down? Yes. The first mortgage still covers 80 percent, but the second lien grows to 15 percent and the down payment shrinks to 5 percent. The second lien is larger, so its monthly cost carries more weight in the comparison against paying PMI.
Does a piggyback second lien get more expensive over time? It can. The CFPB notes these second liens are “often adjustable,” meaning the rate can rise after closing. A HELOC also typically converts from interest-only payments to a fully amortizing payment once its draw period ends, which raises the monthly cost even if the rate never moves.
What happens to my second lien if I refinance my first mortgage? Fannie Mae’s Selling Guide generally requires a resubordination agreement so the second lien keeps its lower-priority position behind the new first mortgage. Some state laws allow the lien to stay in place automatically instead, but you should not assume that applies to you without confirming it with your lender.
Is PMI tax deductible right now? No. The Internal Revenue Service’s (IRS) current Publication 936 states plainly that “the itemized deduction for mortgage insurance premiums has expired,” and that taxpayers “can no longer claim the deduction.” Do not build a piggyback-versus-PMI decision around an expected tax break that current IRS guidance does not support.
Which option should I pick if I am only putting 10 percent down? Run both numbers with your own loan officer using your actual quoted rates, not averages. If the piggyback’s monthly savings are large and you plan to stay in the home for years, it is often the stronger cash-flow choice. If the gap is small, the single loan with PMI is simpler and it disappears on its own.