The real question isn't just "can I afford it?" — it's whether buying a home beats renting and investing the difference in the stock market. Our interactive calculator shows you the exact year buying wins, how much home equity you build, how much total interest you pay, and what your down payment would be worth in the S&P 500 instead. All figures are after-tax — including mortgage interest deductions, property tax deductions, primary residence capital gains exclusion, and capital gains tax on S&P portfolio gains. Buy advantage is ending wealth: buy cash (gross proceeds) minus rent portfolio (S&P after tax). Net P&L (buy) uses only true costs: down, interest (see "Interest paid (cost in P&L)" — principal is already in gross proceeds), tax, and maintenance.
This tool models the full after-tax financial picture of buying a home versus renting and investing — not just your monthly payment.
Set the home price, down payment, mortgage rate, and loan term. Defaults to a 30-year fixed at 7% — adjust to match current rates or quotes you've received.
Enter what you'd pay in rent for a comparable home. The calculator invests your down payment and any monthly savings from renting into the S&P 500 at your chosen return rate.
Set your marginal tax rate, filing status, whether you itemize deductions, and your long-term capital gains rate. These materially affect both sides of the comparison — deductions benefit buyers, capital gains tax hits the rent scenario at exit.
On the Exit Strategy tab, drag the white dashed line to the year you'd plan to sell. The panel below instantly shows after-tax proceeds, S&P portfolio value, net P&L for both scenarios, and which one wins at that exact moment.
In the early years of a mortgage, the vast majority of your payment goes to interest, not equity. On a $450,000 loan at 7%, your first monthly payment of ~$2,994 includes roughly $2,625 in interest and only $369 in principal. You're not building equity fast — you're paying the bank.
This is why buying and selling in 2-3 years is often a financial loss even if the home appreciated. Selling costs (typically 5-7%) can wipe out the thin equity you've built.
A 20% down payment on a $450,000 home is $90,000 that could have been invested. At the S&P 500's historical ~10.5% annual return, that $90,000 becomes roughly $250,000 in 10 years. But at exit, that S&P gain is subject to long-term capital gains tax — which this calculator accounts for, unlike most others.
This is the hidden cost of buying that most calculators ignore completely.
After the 2017 Tax Cuts and Jobs Act nearly doubled the standard deduction, fewer than 10% of taxpayers now itemize. If you take the standard deduction, the mortgage interest deduction has zero value to you. Our calculator defaults to no itemizing — toggle it on only if your total deductions genuinely exceed the standard deduction threshold.
When you do itemize, only the marginal benefit above the standard deduction counts — not the full deduction amount.
One of the most powerful tax benefits of homeownership: when you sell your primary residence, up to $250,000 in capital gains is tax-free (single) or $500,000 (married filing jointly), provided you've lived there for 2 of the last 5 years. For most people in most markets, this means paying zero capital gains tax on sale — a huge advantage over the taxable S&P gains in the rent scenario.
Everything you need to know about the rent vs buy decision and how this calculator works.
The break-even point typically ranges from 4 to 10 years depending on your local market, mortgage rate, appreciation, and rent vs ownership cost. In high-cost cities with low appreciation it can take 7-10 years. In appreciating markets with competitive rates it can be as short as 3-4 years. Use the exit strategy simulator above to find your exact after-tax break-even year.
For most people, no. The 2017 Tax Cuts and Jobs Act raised the standard deduction to $14,600 (single) and $29,200 (married) in 2024. Unless your total itemized deductions — mortgage interest + property taxes (capped at $10,000 SALT) + charitable giving + other — exceed that threshold, you get no benefit from the mortgage interest deduction. Only about 10% of Americans currently itemize. If you do itemize, only the amount above the standard deduction threshold represents actual tax savings.
If you've owned and lived in your home as your primary residence for at least 2 of the last 5 years, you can exclude up to $250,000 (single) or $500,000 (married filing jointly) of capital gains from federal income tax when you sell. This is one of the most significant tax advantages of homeownership. Our calculator applies this exclusion automatically at exit — any gain below the threshold is tax-free, and any gain above it is taxed at your long-term capital gains rate.
No. If you invest your down payment in the S&P 500 and account for taxes on both sides, renting can outperform buying financially in the short to medium term — especially when mortgage rates are high, home appreciation is slow, or rent is significantly cheaper than owning. Buying typically wins over the long term (10+ years) due to forced savings, leverage, and the capital gains exclusion.
In the rent scenario, when you "exit" (i.e., liquidate your S&P portfolio to compare apples-to-apples with the home sale), we calculate the total portfolio gain (portfolio value minus your total contributions — down payment plus monthly savings invested). That gain is subject to long-term capital gains tax at your chosen rate (0%, 15%, or 20% federally, depending on income). This is a real cost the rent scenario faces that most calculators ignore.
The true cost of homeownership includes: your down payment, all monthly mortgage payments (principal + interest), property taxes (typically 1-2% annually), maintenance and repairs (typically 1% annually), and selling costs when you exit (agent commissions + closing costs, typically 5-7% of sale price). Our calculator accounts for all of these, plus tax deductions if you itemize, and applies the capital gains exclusion at sale.
This calculator uses standard mortgage amortization formulas, compound growth models, and US federal tax rules. Results are financially accurate given the inputs provided but are projections based on assumed constant rates. It does not account for state income taxes, AMT, HOA fees, inflation adjustments, or the SALT deduction cap interplay in detail. It is a planning and comparison tool, not tax or financial advice. Consult a CPA or financial advisor for your specific situation.