Real Estate Tax Calc
What pre-tax cash-on-cash captures
The standard formula — annual cash flow ÷ cash invested — uses pre-tax cash flow. It ignores both the tax you owe on net rental income and the tax savings from depreciation. Pre-tax cash-on-cash is fast and useful for comparing deals, but understates the true return for taxpayers who can put depreciation deductions to use.
How depreciation improves after-tax return
Depreciation is a non-cash deduction that reduces taxable income. Even when a property generates positive cash flow, depreciation often creates a paper loss that lowers your tax bill. Those tax savings are real dollars. After-tax cash-on-cash adds those savings back to the numerator, giving a truer picture of what the investment earns.
When the difference is largest
The gap between pre-tax and after-tax return is widest when depreciation is large relative to cash flow (high-basis property, early years in ownership), when you're in a higher tax bracket, and when passive activity rules allow you to use the deductions. The gap narrows when passive losses are suspended or your bracket is low.
A worked example
Suppose you invest $80,000 to buy a $320,000 rental and it throws off $6,400 of pre-tax annual cash flow — an 8% pre-tax cash-on-cash return. Now layer in taxes. The building portion (say $256,000) depreciates over 27.5 years, roughly $9,300/year. That deduction, plus mortgage interest and operating expenses, can push taxable rental income to about negative $3,000 even though you pocketed $6,400 in cash. If you're in the 24% bracket and can use that paper loss, it shelters other income and saves about $720 in tax. After-tax cash flow becomes $6,400 + $720 = $7,120, lifting the return to 8.9%.
Building the after-tax numerator step by step
Start with pre-tax cash flow. Then adjust for the tax effect of the property's taxable result: (a) compute taxable rental income = rents − operating expenses − mortgage interest − depreciation; (b) multiply by your marginal rate to get tax owed (a positive result) or tax saved (if it's a usable loss); (c) subtract tax owed from, or add tax saved to, pre-tax cash flow. Divide the result by your cash invested. The only new inputs beyond a standard cash-flow model are depreciation and your marginal tax rate — everything else you already have.
Your marginal bracket drives the size of the benefit
The tax shield is worth your marginal rate times the deduction. A $9,300 depreciation deduction saves a 37% taxpayer about $3,441 but a 12% taxpayer only $1,116. High earners therefore see the widest gap between pre-tax and after-tax return — one reason depreciation is so valuable to them. State income tax adds to the shield: an investor in a 9.3% state bracket stacks additional savings on top of the federal benefit, widening the after-tax advantage further.
Passive activity rules can trap the benefit
The after-tax boost only materializes if you can actually use the paper loss. Rental losses are generally passive under IRC §469. If your modified AGI exceeds $150,000 and you're not a real estate professional, the loss is usually suspended — it carries forward but doesn't cut this year's tax, so your after-tax return equals your pre-tax return for now. The special $25,000 allowance for active participants phases out between $100,000 and $150,000 of MAGI. Model the shield only to the extent you can deduct it this year.
Depreciation recapture: a deferred, not free, benefit
The savings from depreciation are partly a timing benefit. When you sell, the depreciation you took (or could have taken) is recaptured — the gain attributable to it is taxed as unrecaptured Section 1250 gain at a federal rate up to 25%. A true after-tax return over the full hold should account for that future bill. The benefit is still real, thanks to the time value of money and because your recapture rate (max 25%) may be lower than the ordinary rate at which you sheltered income — but it's deferral plus rate arbitrage, not a permanent free deduction.
Planning tips to capture the after-tax edge
A few moves widen the after-tax return: run a cost segregation study to front-load depreciation on high-basis properties; qualify as a real estate professional (or use the short-term rental rules) to make losses non-passive; harvest suspended losses in a year you have passive income or when you sell; and consider a 1031 exchange at sale to defer recapture and capital gain. Above all, compare deals on the same basis — pre-tax to pre-tax, or after-tax to after-tax — and never mix the two, or you'll flatter one property over another for no real reason.
A high-bracket example with suspended losses
Take a 37% earner who buys a $600,000 rental. Cost segregation and bonus depreciation produce a $120,000 first-year paper loss, but the investor's MAGI is well above $150,000 and they aren't a real estate professional, so the loss is passive and suspended. Their after-tax cash-on-cash that year equals pre-tax — the shield is trapped. Fast-forward to a year they sell another passive investment at a gain, or qualify for real estate professional status: the suspended loss is freed, worth roughly 37% × $120,000 = $44,400 when released. The benefit was never lost, only deferred until it could be used.
QBI and the after-tax picture
Positive rental income may qualify for the Section 199A qualified business income deduction — up to 20% of net rental income — if the activity rises to a trade or business (the rental real estate safe harbor of Rev. Proc. 2019-38 is one path). A 20% QBI deduction on profitable rental income raises after-tax cash-on-cash in the years a property shows a profit, partially offsetting the tax on that income. It's most relevant later in the hold, once depreciation no longer shelters the income.
The 3.8% net investment income tax
High earners face the net investment income tax (NIIT) — an extra 3.8% on net investment income once MAGI exceeds $200,000 (single) or $250,000 (married filing jointly). Passive rental income and the gain on sale generally count, so a full after-tax model for a high earner should add 3.8% to the effective rate on taxable rental income and on the eventual gain. Real estate professionals who materially participate may avoid NIIT on rental income, another reason the designation matters for after-tax returns.
Looking at after-tax return over the full hold
A single year's after-tax cash-on-cash understates the story. Over a multi-year hold, the tax shield is largest early (more depreciation, more interest) and shrinks as the loan amortizes and, eventually, as the property is fully depreciated. Meanwhile taxable income — and tax owed — rises. A thorough investor models each year's after-tax cash flow and the after-tax sale proceeds (net of recapture and capital gains, or deferred via 1031), then computes an after-tax internal rate of return. That is the number that truly compares real estate against other after-tax investments.
Principal paydown: a separate source of return
Neither pre-tax nor after-tax cash-on-cash captures equity build from principal paydown — the portion of each mortgage payment that reduces your loan balance. That's a real return funded by your tenants, but it's not cash in your pocket this year, so it sits outside the cash-on-cash metric. When comparing the full return of a leveraged rental against other investments, add principal paydown (and appreciation) alongside after-tax cash flow, or move to a total-return or after-tax IRR framework. Cash-on-cash measures yield on cash, not the whole picture.
Comparing real estate to taxable alternatives
The reason after-tax return matters is comparability. A 4% municipal bond may be federally tax-free, while a 5% corporate bond is fully taxable — after tax, they can be similar. Rental real estate sits in between: cash flow is often sheltered by depreciation in early years, making its after-tax yield higher than its pre-tax yield, then more like ordinary income later. To decide whether a rental beats a brokerage account or a bond ladder, put every option on an after-tax basis; comparing a rental's pre-tax return to a bond's after-tax return is apples to oranges.
Don't forget: allowed-or-allowable depreciation
A crucial wrinkle for after-tax planning is that the IRS assumes you took depreciation whether you did or not. At sale, recapture is calculated on depreciation allowed or allowable — so skipping depreciation to boost reported cash flow doesn't spare you the recapture, it just forfeits the deduction. This means the depreciation tax shield in your after-tax return isn't optional: you should claim it every year to actually receive the benefit you'll be taxed on anyway. If you missed depreciation in prior years, Form 3115 (change in accounting method) can let you catch up in a single year.
Frequently asked questions
Should I use pre-tax or after-tax cash-on-cash?
Pre-tax is the standard for quick comparisons. After-tax is more accurate for a full investment analysis, especially if you can use depreciation deductions.
How does depreciation affect after-tax return?
Depreciation creates a paper loss that offsets rental income, reducing your tax bill — effectively adding to your after-tax cash flow.
Is after-tax cash-on-cash always higher than pre-tax?
Usually in the early years, because depreciation shelters income. But if the property shows taxable income — little depreciation left, low leverage — you may owe tax, making after-tax return lower than pre-tax.
Do I need a cost segregation study to see a benefit?
No. Standard 27.5-year depreciation already creates a shield. A cost segregation study simply accelerates it, enlarging the early-year after-tax advantage on higher-basis properties.
Does the after-tax benefit disappear at sale?
Not entirely. Depreciation recapture claws back part of it, but you still gained years of deferral and possibly a lower recapture rate than the rate you deducted at. A 1031 exchange can defer the recapture indefinitely.
Does the 3.8% NIIT apply to my rental?
Often, yes, for higher earners. Passive rental income and gain on sale generally count as net investment income subject to the 3.8% surtax above the MAGI thresholds. Real estate professionals who materially participate may be able to exclude the rental income from NIIT.
Can positive rental income get the 20% QBI deduction?
It can, if the rental activity qualifies as a trade or business — the Section 199A rental safe harbor is one route. The deduction lifts after-tax return in profitable years, which typically arrive later in the hold.
If I skip depreciation, do I avoid recapture?
No. Recapture is based on depreciation allowed or allowable, so the IRS treats you as having taken it even if you didn't. Skipping it forfeits the deduction while leaving the recapture — always claim it, and use Form 3115 to catch up missed years.
Sources
Educational information and estimates only. Not tax advice. Tax rules change and vary by situation; consult a qualified tax professional before acting.