Down payment myths, busted
The 20% rule is the single most repeated piece of mortgage advice in America. It's also the most outdated. Modern mortgage products let you put down 3% to 10% routinely, and the math on whether that's smart is more nuanced than "avoid PMI."
Where the 20% rule came from
Lenders historically required 20% down because higher down payments correlate with lower default rates. PMI, private mortgage insurance, was introduced as a way to insure the lender against default when you put down less.
PMI is paid by you, the borrower, but it protects the lender, not you. That's why it gets a bad reputation.
What PMI actually costs
PMI typically costs 0.3–1.5% of the loan amount per year, paid monthly. On a $500k loan, that's $125–$625/month.
It also drops automatically once your loan-to-value ratio reaches 78–80%, which on most amortizing loans happens within 5–10 years even without home appreciation.
The real opportunity cost question
Putting 5% down on a $500k home keeps $75k in your pocket vs. putting 20% down. If you invest that $75k at a 7% real return, in 10 years it's worth ~$148k.
Over those same 10 years, you'd pay roughly $40k–$60k in PMI. The math frequently favors the lower down payment, especially if you have other high-priority uses for the cash (emergency fund, retirement, business).
When 20% does still make sense
If you're in a slow-appreciation market and don't have a strong investment alternative, 20% reduces your monthly payment, eliminates PMI, and gives you a stronger offer in competitive bidding.
Jumbo loans (above ~$766k conforming limit in most areas) often require 10–20% down regardless. Some loan products are only available with higher down payments.
Programs that go lower
FHA: 3.5% down, more lenient credit. Has its own mortgage insurance that doesn't drop off automatically.
VA: 0% down for eligible veterans. No mortgage insurance.
Conventional 97: 3% down for first-time buyers, regular PMI rules.
Doctor / professional loans: low or no down payment for specific careers.
What to do
Run the numbers both ways using our mortgage calculator and our affordability calculator. Compare the monthly payment, total interest paid, and what the freed-up cash could earn.
Then talk to a broker, they'll know the niche programs and help you find the option that fits your situation.