10% Down vs 20% Down: Which Costs More Over Time

On a $700,000 home at today’s 6.53% rate, choosing 10% down instead of 20% costs an extra $89,247 over five years — before accounting for what you could have earned investing the $70,000 difference. Once opportunity cost enters the model, the answer stops being obvious in either direction.

The “always put 20% down” rule persists because it’s simple. It’s also frequently wrong for households with liquidity needs, equity in other assets, or higher-yield alternatives for that capital. The math below runs the actual comparison — not the marketing version.

Key Figures at a Glance

Sources: Freddie Mac PMMS, May 28, 2026; PMI rate modeled at 0.70% annually (Urban Institute Housing Finance Policy Center range: 0.46%–1.50%); P&I calculated on 30-year amortization at 6.53%.

The Rate Environment Shapes Everything

Freddie Mac’s PMMS placed the 30-year fixed-rate mortgage at 6.53% as of May 28, 2026 — up from 6.51% the prior week, and meaningfully below the 6.89% recorded a year earlier. At this rate, every $100,000 of loan principal costs approximately $635 per month in principal and interest (P&I).

The 10% borrower carries a $70,000 larger loan. At 6.53%, that difference alone generates an additional $445/month in P&I versus the 20% scenario — before PMI. Rates near 6.5% make larger loans expensive to carry, which tilts the raw monthly math toward putting more down. But raw monthly math is only part of the picture, because the $70,000 not deployed as down payment doesn’t disappear — it exists as investable capital.

Households targeting a understanding of how rate changes alter monthly payments should run this model at the rate they’re actually quoted, since even a 0.5% swing materially changes the 5-year cost differential.

PMI: The Real Cost and When It Dies

Private mortgage insurance on a conventional loan runs 0.46%–1.50% of the loan amount annually, according to the Urban Institute’s Housing Finance Policy Center. The actual rate you pay depends on credit score, loan size, and the specific insurer. A borrower with a 760+ credit score and 10% down will land closer to 0.50%–0.75%; someone at 680 with the same down payment might see 1.00%–1.20%.

For the $700,000 example above, using a mid-range PMI rate of 0.70%: the $630,000 loan generates $4,410 in annual PMI, or $368/month. Over 12 months, that’s $4,410 you won’t see back. Across five years — before PMI terminates — you’re looking at roughly $22,050 in PMI premiums, declining slightly each year as the loan balance falls.

Under the Homeowners Protection Act of 1998, lenders must automatically terminate PMI once the LTV ratio reaches 78% of the original purchase price, based on the scheduled amortization. Separately, borrowers may request cancellation when LTV hits 80% — typically supported by a new appraisal if appreciation has accelerated paydown. On a $700,000 home with $630,000 borrowed at 6.53%, standard amortization reaches 78% LTV at approximately month 98 (just over 8 years), absent prepayment or appreciation. With assumed 3% annual home appreciation, the LTV could reach 80% as early as year 4–5, enabling a borrower-requested cancellation well ahead of schedule.

The full mechanics of PMI cost and the exact cancellation timeline matter here: the faster you can exit PMI, the more the 10%-down calculus improves.

Five-Year Total Cost: The Model

Five years is the right analysis window for most primary-residence buyers — it captures the full PMI burden of the early loan period while remaining shorter than the median hold period for owner-occupied homes. The table below models cumulative costs at two price points: $600,000 (more accessible market) and $800,000 (upper mid-range for $150k+ households in high-cost metros).

Rate: 6.53% (Freddie Mac PMMS, May 28, 2026). PMI estimated at 0.70% of loan annually for 10%-down scenarios; declines slightly with balance but modeled at approximate average. 5-year PMI assumes PMI persists the full 60 months (conservative; borrower-requested cancellation at 80% LTV is possible earlier with appreciation). P&I figures derived from standard 30-year amortization. Figures are rounded to the nearest dollar.

At $600,000, the 10%-down scenario costs $41,700 more over five years in combined P&I and PMI. At $800,000, the gap widens to $55,620. These are real dollars leaving the household — not equity, not investment returns.

Now the other side of the ledger: the 20%-down buyer at $600,000 deployed an additional $60,000 at closing versus the 10%-down buyer. Invested in a diversified portfolio at a conservative 7% annualized return over five years, that $60,000 grows to approximately $84,153 — generating $24,153 in gains. At $800,000, the differential is $80,000 invested, growing to approximately $112,204 — a $32,204 gain. Those opportunity costs partially — and in some scenarios fully — offset the PMI and interest premium of going in with less down.

Break-Even: When Does 20% Down Pay for Itself?

The break-even calculation turns on one variable: what return the freed capital earns. At a 7% assumed investment return, the opportunity cost of the extra down payment at $600,000 compounds to $24,153 over five years. The 10%-down premium (extra interest + PMI) over five years is $41,700. So at 7%, the 20%-down buyer still comes out ahead by roughly $17,547 over five years at $600,000.

The calculus shifts when the assumed return rises. At a 10% return, the $60,000 held back by the 10%-down buyer grows to $96,631 — generating $36,631 in gains that close most of the gap. At 12% return, the freed capital more than offsets the PMI premium entirely within five years. Whether a 10–12% return is realistic for a specific household’s portfolio is a separate question. For $150k+ households with meaningful equity allocation in index funds or other appreciating assets, these are not unreasonable assumptions — but they depend heavily on sequence-of-returns risk and the time horizon.

The break-even also shifts dramatically if the buyer can exit PMI early. A borrower who buys a $600,000 home with 10% down, benefits from 4% annual appreciation, and requests cancellation at 80% LTV might eliminate PMI in 3.5 years rather than 8+. That saves $10,500–$13,000 in PMI premiums and compresses the total 10%-down premium substantially. Anyone thinking through a PMI cost and break-even timeline at lower price points will find the same principle holds: early PMI exit is the single most powerful variable in the model.

Finluxy First Home Cash Requirement

The comparison above models P&I and PMI — but neither scenario gets you to closing without significantly more cash. The Finluxy First Home Cash Requirement captures total liquid capital needed at closing: down payment + closing costs + prepaids + inspection/repair reserve.

Closing costs estimated at 3% of loan amount (CFPB guidance: 2%–5% range; Bankrate 2025 national average $4,661 for lower-priced transactions, percentage model used here for higher-value loans). Prepaids include first-year homeowner’s insurance and 2–3 months property tax escrow at national averages. Inspection/repair reserve is a conservative flat figure. Income benchmark: $200,000 gross annual.

The 20%-down path at $800,000 demands the equivalent of 11.4 months of gross income at $200,000 in liquid assets at closing. That figure — nearly a year of pre-tax earnings in cash — is what stops many $150k+ households from choosing the larger down payment, even when the 5-year math nominally favors it. The full cash-to-close breakdown on a $600k home and the detailed cash requirements at $350k show how the Finluxy First Home Cash Requirement scales across price points.

What the Data Overlooks — and Most Coverage Gets Wrong

The standard framing of this decision treats PMI as pure waste. It isn’t. PMI functions as the cost of liquidity preservation. A household that puts 10% down and keeps $70,000 invested has optionality the 20%-down buyer doesn’t: emergency reserves, the ability to fund a renovation without a HELOC, flexibility to rebalance a portfolio. Illiquidity risk in real estate is real — the equity locked in a home cannot be accessed quickly or cheaply in a market downturn.

NAR’s 2025 Profile of Home Buyers and Sellers reported that the median down payment among first-time buyers reached 10% — the highest since 1989 — even as first-time buyers fell to just 21% of all buyers. The buyers who are transacting have already internalized this trade-off. They’re putting down less not because they can’t afford more, but because they’re managing total balance sheet risk. That’s a financially sophisticated move that the “always do 20%” crowd consistently misreads as constraint rather than strategy.

For households evaluating what income level supports what purchase price, the income-to-purchase-price analysis for $150k households provides an income-anchored framework that reframes the question entirely.

The $150k+ Household Decision Framework

For households earning $150,000 or more, the 10% vs. 20% down decision is a capital allocation question, not a qualification question. You likely qualify under either scenario. The question is where the marginal dollar earns more — locked as home equity at a cost basis of the prevailing mortgage rate, or deployed elsewhere.

Three factors push toward 10% down for this income cohort. First, liquidity headroom: at $150k–$200k income, eight months of gross income in cash (the 20%-down requirement at $600k) is a significant concentration of liquid assets in a single illiquid asset. Second, investment horizon: if the household plans to hold the home seven or more years, PMI’s total cost is diluted across a long time base, and appreciation-driven LTV improvement may eliminate it in years 3–5. Third, alternative returns: households with access to tax-advantaged accounts, employer match opportunities, or high-yield investment vehicles may earn more per dollar invested than the mortgage rate implies.

Three factors push toward 20% down. Rate sensitivity: at 6.53%, carrying an extra $70,000 in mortgage debt costs $445/month in pure interest-equivalent load. A household that values cash flow certainty over portfolio upside benefits from the lower PITI. PMI duration uncertainty: if home values stagnate or decline, PMI cancellation at 80% LTV gets pushed further out — potentially to the full 8+ year auto-termination timeline. And some buyers simply dislike the administrative overhead of managing PMI removal. The FHA versus conventional loan cost comparison is worth running if credit profile makes FHA competitive; FHA’s mortgage insurance premium structure behaves very differently from conventional PMI.

The cleanest version of this analysis for a $150k+ household: model the freed capital at a conservative return assumption (5%–6%), add back the PMI and interest premium at your specific loan size, and compare net positions at years 3, 5, and 7. If you can exit PMI by year 4 through a combination of payments and appreciation, the 10%-down path can be net-neutral to favorable even against a 5% opportunity cost assumption. If you’re buying in a flat or declining market where appreciation won’t accelerate LTV improvement, 20% down wins more clearly.

Buyers weighing the same question at different income levels will find the math shifts significantly — the purchase power analysis at $100k income shows why the liquidity constraint is far more binding at lower income brackets, making the 10%-down path less of a strategic choice and more of a necessity.