Mortgage ToolkitHow the Rent vs Buy Calculator Works
This calculator runs a month-by-month simulation of two parallel paths: buying a home with a mortgage, or renting and investing the money you'd otherwise put toward a down payment and ownership costs. The buyer path tracks home equity (home value minus remaining loan balance) as the mortgage amortizes and the home appreciates. The renter path starts with that same down payment amount invested, then each month adds the surplus — the buyer's all-in housing cost (mortgage, tax, insurance, HOA, maintenance) minus rent — to the renter's portfolio. When owning costs more than renting in a given month, the renter invests the difference; when renting costs more, the renter's portfolio effectively draws down relative to the buyer. Both paths use the same starting cash, so the comparison isn't biased toward either side by default.
The result is a break-even point: the month where the buyer's equity first catches up to and passes the renter's portfolio value. Before that point, renting and investing usually comes out ahead because you haven't recovered your closing costs yet. After it, buying tends to pull ahead as equity and appreciation compound. The recommendation card above the fold gives you the verdict immediately; the break-even timeline, decision explanation, and wealth breakdown below walk through exactly how that verdict was reached.
Understanding the Results
The recommendation card shows the winning path, the wealth advantage in dollars, the break-even year, and a confidence rating — high confidence means the gap between renting and buying is large relative to the total wealth involved; low confidence means the two paths land close enough that the decision could reasonably go either way. The monthly housing cost card breaks down exactly what ownership costs you today: mortgage principal and interest, property tax, insurance, HOA, and maintenance, summed into a single total you can compare directly against your rent. The wealth breakdowncard shows where each side's final number actually comes from — home equity and appreciation for the buyer, contributions and investment gains for the renter — rather than just a single net figure.
The charts plot buyer equity against the renter's portfolio over the full horizon, with the break-even point marked directly on the net worth chart, plus cumulative cash spent on each path and home equity growth on its own. The year-by-year table below gives you the same numbers at annual resolution if you want to check a specific year without hovering over the chart.
What Is Opportunity Cost?
Opportunity cost is the return you give up on money by spending it one way instead of another. A down payment and ongoing ownership costs aren't just expenses — they're capital that could otherwise be invested. This calculator makes that opportunity cost explicit: the investment returninput models what your down payment and any monthly surplus could have earned if invested instead of tied up in a home. Long-term stock market returns have historically averaged around 7–10% annually before inflation, though real returns vary significantly by period and asset mix — this is the single biggest lever in whether renting or buying wins in the simulation, so it's worth setting it deliberately rather than leaving the default in place.
How Home Appreciation Affects Wealth
Home appreciation compounds on your home's full value, not just your equity — which is what makes leverage work in a buyer's favor when prices rise. A home bought with a 20% down payment that appreciates 3% a year is effectively earning that 3% on the entire home value while you've only put up a fifth of the cash, amplifying your return on the money actually invested. Average historical appreciation varies a lot by location, so it's worth checking local trends for your specific market rather than assuming a national average applies. Try the +2% Appreciation and −2% Appreciation quick-scenario buttons above to see exactly how sensitive your result is to this one assumption.
How Rent Inflation Changes the Result
Rent typically rises every year, while a fixed-rate mortgage payment doesn't (aside from tax, insurance, and HOA increases). Over a long horizon, this compounding gap is one of the strongest arguments for buying: a renter's housing cost keeps climbing indefinitely, while a buyer's core mortgage payment is locked in. The annual rent increase input models this directly, and the +2% Rent Increase and +5% Rent Increasequick-scenario buttons let you see how a faster-rising rental market shifts the break-even point in the buyer's favor.
Understanding Closing Costs
Closing costs are a one-time expense at purchase — typically 2–5% of the home price — covering loan origination, appraisal, title insurance, and other lender and legal fees. They're the main reason renting usually looks better in year one: you haven't had time to recover that upfront cost through equity and appreciation yet. Selling costs (typically agent commissions and closing fees, 5–7% of sale price) work the same way in reverse, reducing your net proceeds if you sell. Both are already factored into the break-even and wealth breakdown calculations above. If you're also comparing mortgage offers with different closing costs, the loan comparison calculator runs the same kind of break-even math specifically for that decision.
Property Taxes Explained
Property tax is set by your local government as a percentage of assessed home value and is one of the largest recurring ownership costs after the mortgage itself. Rates vary enormously by location — from under 0.5% of home value per year in some areas to well over 2% in others — so it's worth checking your specific local rate rather than relying on the default. This calculator applies your property tax percentage to the home's current (appreciating) value each month, so the tax bill rises over time along with the home's value, matching how most jurisdictions actually reassess property.
Maintenance Costs
Ongoing maintenance and repairs are easy to underestimate when comparing renting to buying, since a landlord absorbs these costs for a renter. A common rule of thumb is around 1% of the home's value per year, though actual costs vary by the age, size, and condition of the property — an older home or one with a pool, extensive landscaping, or aging major systems (roof, HVAC) can run meaningfully higher. This calculator applies your maintenance percentage to the home's current value each month, alongside property tax and insurance, so it's reflected in both the monthly housing cost breakdown and the total cost of ownership over your horizon.
Investment Return Assumptions
The investment return you assume for the renter's portfolio has an outsized effect on the outcome, because it compounds over the full comparison horizon just like home appreciation does for the buyer. A diversified stock portfolio has historically returned somewhere in the 7–10% range annually over long periods before inflation, but that includes significant year-to-year volatility that a single average rate doesn't capture — and past performance doesn't guarantee future returns. If you'd realistically keep the money in a savings account or bonds instead of the market, use a more conservative rate; if you're confident in a long, disciplined investing horizon, a stock-market-level return is more representative of the renter's actual opportunity.
Factors That Affect the Decision
Beyond the numbers, a handful of practical factors tend to tip the decision one way or the other: how long you plan to stay in the home (short stays rarely recover closing costs), how stable and predictable your income is (a fixed mortgage payment offers certainty a variable rent doesn't), how much you value flexibility to relocate for work or life changes, and your local rent-to-price ratio (in some markets rent is unusually cheap relative to buying, and vice versa). Once you have a purchase scenario you're serious about, running the exact numbers through the mortgage calculator gives you a more detailed monthly payment breakdown including PMI, and checking today's mortgage rates ensures the rate you're modeling here is realistic for current market conditions.
If you already own and are wondering whether a lower rate would change this calculus, the mortgage refinance calculator shows whether refinancing your current loan is worth it. If you're deciding between a 15-year and 30-year mortgage as part of your buying scenario, the amortization calculator shows the full payment-by-payment schedule for either term, and the overpayment calculator shows how extra payments would accelerate your equity growth beyond what this tool models by default.
Common Mistakes When Comparing Renting and Buying
The most common mistake is comparing rent directly against a mortgage payment alone, ignoring property tax, insurance, maintenance, and HOA — which together can add 30–50% on top of the mortgage payment itself. A second mistake is assuming a home price appreciation rate without checking local historical trends, since national averages can be very different from a specific city or neighborhood's trajectory. A third is ignoring opportunity cost entirely — treating a down payment as if it simply disappears, rather than modeling what it could have earned invested elsewhere, which is exactly what the renter path in this calculator is designed to correct for. A fourth is underestimating how long it takes to break even: moving or selling before the break-even point (often visible directly on the chart above) usually means renting would have come out ahead financially, even if buying felt like the more permanent, stable choice.