"You need 20% down to buy a house." It's one of the most repeated lines in real estate, and for a lot of buyers, it's simply not true. Let's run the actual numbers on a $740,000 home and see what 20% really buys you.
Putting 20% down isn't wrong, but it's not automatically right, either. The decision comes down to math and timing, not a rule of thumb. Here's the full picture.
First, the part nobody tells first-time buyers
You don't need anywhere near 20% to actually buy. As a first-time buyer, the minimums are far lower:
So the real question was never "can I buy with less than 20%?", you can. The question is whether putting more down is worth it. Let's run that math.
The $740,000 example
Say you're buying a $740,000 home. Here's what your cash looks like at 20% down versus a low-down-payment option:
| 20% down | 3% down | |
|---|---|---|
| Down payment | $148,000 | $22,200 |
| Loan amount | $592,000 | $717,800 |
| Monthly PMI | $0 | ~$250 |
| Cash still in your pocket | $0 | $125,800 |
To avoid roughly $250 a month in PMI, the 20%-down buyer hands over about $125,800 more up front, that's the cash a 3%-down buyer keeps in their pocket. It's a six-figure decision to save a couple hundred dollars a month. So is it worth it? That depends entirely on how long you'll stay.
Myth #1: "20% down saves you a fortune on PMI"
The PMI you're avoiding might be around $250/month. But you're tying up roughly $125,800 to do it. And here's the part nobody mentions: on a conventional loan, PMI isn't permanent, it falls off automatically once you reach about 20% equity. Through normal payments alone that can take ~11 years, so the savings only start showing up around year 12.
How long are you actually staying?
This is the question that decides everything. If it takes until year 12 for 20% down to pay off through PMI savings, but you're like most buyers, you'll move long before then:
Most people move in 4 to 6 years, a bigger place when the family grows, a smaller one when it shrinks, a new city for work. If you sell in year 5, you never reach the point where that extra $125,800 paid off. You simply tied up six figures of cash for a benefit you left before collecting.
Myth #2: "20% down gets you a much better rate"
Not always. Sometimes the interest rate doesn't change at all between 5% and 20% down. When that's the case, the only real savings from 20% down is removing the PMI, so the rate argument falls apart, and you're back to the same question: is removing ~$250/month worth $125,800 in cash?
What that $125,800 could do instead
Cash you don't sink into a down payment doesn't disappear, it stays liquid and useful. Before locking it into your home's equity, it's worth asking whether it does more for you elsewhere:
- An emergency reserve. When the water heater or roof fails, that cash covers it, instead of reaching for a credit card or a high-interest loan to pay for the repair.
- Other goals. Investing, a business, paying off higher-interest debt, or simply breathing room in your monthly budget.
- Staying flexible. Money tied up in equity is hard to reach. Money in the bank gives you options if life changes.
The takeaway
Keeping a healthy reserve can be smarter than maxing out your down payment. The goal isn't to put down as much as possible, it's to put down the right amount for your life.
So, 20% or 3%? It depends on you
There's no universal answer, only the one that fits your numbers and your timeline. Twenty percent down can be the right move if you're staying long-term and have plenty of reserves to spare. A low down payment can be far smarter if you value flexibility, expect to move in a few years, or would rather keep that cash working and protected.
The mistake is assuming 20% is the only "responsible" choice. It isn't. When your financials and your timeframe actually line up, the right number might be a lot lower than you were told, and that could be the difference between buying now and waiting years to save a down payment you didn't need.
Let's run your real numbers
Every situation is different. We'll compare your down-payment options side by side, so you put down the amount that's right for your life, not a myth.