"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.