Real Estate Tax Calc
Step 1 and 2: Amount realized and adjusted basis
Amount realized = selling price − selling costs (commissions, attorney fees, transfer taxes, other closing costs). This is what you \"net\" from the transaction for tax purposes.
Adjusted basis = original purchase price + capital improvements − total depreciation claimed (\"allowed or allowable\"). Depreciation reduces your basis each year you own the property, even if you forgot to claim it.
Step 3: Total gain and how it splits
Total gain = amount realized − adjusted basis. This gain splits into two buckets: (1) Unrecaptured Section 1250 gain — equal to the depreciation claimed, taxed at up to 25%; and (2) Remaining long-term capital gain — the appreciation above original cost, taxed at 0%, 15%, or 20% based on your income.
Example: Paid $320,000, claimed $60,000 depreciation (adjusted basis = $260,000), sold for $450,000 with $15,000 selling costs (amount realized = $435,000). Total gain = $175,000. Recapture slice = $60,000 (taxed at 25% = $15,000 federal). Capital gain slice = $115,000 (taxed at 15% for a middle-income seller = $17,250). Total federal tax: roughly $32,250 — before the 3.8% NIIT and state taxes.
Step 4: State taxes and NIIT
Many states tax the full gain as ordinary income at rates up to 13.3% (California) with no special recapture cap. The federal 3.8% Net Investment Income Tax applies if your MAGI exceeds $200,000 (single) or $250,000 (married). Budget for these separately from the federal capital-gains estimate.
Building your adjusted basis correctly
Getting adjusted basis right is where most sale calculations go wrong, and every dollar of overstated basis is a dollar of gain you forgot to report — or a dollar of tax you overpaid. Start with the original purchase price, then add the acquisition costs you capitalized at closing (title insurance, recording fees, transfer taxes you paid as buyer, legal fees, and survey costs). Add every capital improvement made over the years — a new roof, an addition, a kitchen remodel, new HVAC — but not routine repairs, which were already deducted. Subtract all depreciation claimed or allowable, including the partial year in the year of sale and any bonus or Section 179 taken on cost-segregated components. If you ever took a casualty loss deduction or received insurance proceeds you did not reinvest, adjust for those too. Remember that only the building portion was depreciated; the land basis is unchanged, but both land and building bases combine into your total adjusted basis at sale.
What counts as a selling expense
Selling expenses reduce your amount realized, so listing them completely directly lowers your gain. Deductible selling costs generally include real estate agent commissions (often the largest item, at 5–6% of price), attorney and closing-agent fees, title insurance you pay as seller, transfer and documentary stamp taxes, recording fees, and any seller-paid points or buyer credits negotiated into the deal. Advertising and staging costs directly tied to the sale can also qualify. What does not reduce the gain: prorated property taxes and mortgage interest (those are deducted separately), loan payoff amounts (repaying the mortgage principal is not an expense), and repairs made to spruce up the property that are really deductible or capital in nature. Keep the settlement statement (Closing Disclosure) — it itemizes nearly every deductible selling cost in one place.
A fuller end-to-end worked example
You bought a rental for $300,000, paid $6,000 of capitalized closing costs, and later added a $40,000 addition — a cost basis of $346,000. Over the years you claimed $85,000 of depreciation, so your adjusted basis is $261,000. You sell for $520,000 and pay $34,000 in commissions and closing costs, making your amount realized $486,000. Total gain is $486,000 − $261,000 = $225,000. Of that, the $85,000 of depreciation is unrecaptured Section 1250 gain taxed at up to 25% (about $21,250 federal), and the remaining $140,000 is long-term capital gain taxed at 15% for a middle-income seller (about $21,000). Add the 3.8% NIIT on the gain if your income is high (roughly $8,550) and your state's tax on the full $225,000, and the all-in bill can approach or exceed $60,000 — which is why net-proceeds planning before you list matters so much.
Spreading the gain with an installment sale
If you finance the sale yourself and collect the price over several years, the installment method under Section 461/453 lets you report the capital-gain portion as you receive principal, potentially keeping you in lower brackets and below NIIT thresholds each year. You report it on Form 6252, applying a gross-profit percentage to each year's principal. The catch: Section 453(i) requires all depreciation recapture to be recognized in the year of sale, so the 25%-rate slice cannot be spread — you pay that up front even if you receive little cash that year. An installment sale is most attractive when the recapture is small relative to the capital gain, or when smoothing income across years produces a meaningfully lower blended rate.
Ways to reduce or defer the tax
Several levers can shrink the check. A 1031 exchange defers the entire gain — recapture and capital gain — if you roll the full proceeds into like-kind real estate on the required timeline. Suspended passive losses from this property (and, on a full disposition to an unrelated party, from your other passive activities) are generally freed in the year of sale and can offset the gain — a benefit many sellers forget to claim. You can also harvest capital losses elsewhere in your portfolio to offset the capital-gain portion (though losses offset recapture only to a limited degree). Timing the sale into a lower-income year, or after retirement, can drop your capital-gains rate. And if the property was once your home, part of the gain may qualify for the Section 121 exclusion, subject to the rules that carve out depreciation and periods of non-qualified use.
Estimated taxes and when the bill comes due
A large rental sale can create a tax bill far bigger than your normal withholding covers, and the IRS expects payment as you go. To avoid an underpayment penalty, make a quarterly estimated payment for the quarter in which the sale closes, or increase withholding elsewhere. The safe harbors: pay at least 90% of the current year's tax, or 100% of last year's tax (110% if your prior-year AGI exceeded $150,000), to sidestep the penalty even if you still owe a balance in April. Set the estimated-tax money aside from the sale proceeds at closing — before the cash gets spent or reinvested — so the payment is there when the quarterly deadline arrives.
How the sale is reported
A rental sale is reported primarily on Form 4797 (Sales of Business Property), which separates the ordinary-income recapture from the Section 1231 gain. The unrecaptured Section 1250 portion is computed on the Unrecaptured Section 1250 Gain Worksheet in the Schedule D instructions and carried to Schedule D, where it is taxed at up to 25%. The long-term capital gain flows to Schedule D as well and is taxed at 0/15/20%. If you used the installment method, add Form 6252; if you did a 1031 exchange, add Form 8824. Getting the forms right ensures the gain is split correctly between the recapture and capital-gain rates rather than being over-taxed at ordinary rates.
If the rental was once your home: the Section 121 wrinkle
If you lived in the property as your primary residence before renting it out, part of your gain may qualify for the Section 121 exclusion — up to $250,000 single or $500,000 married — provided you owned and used it as your main home for at least 2 of the 5 years before the sale. Two important limits apply to a former rental. First, the exclusion never shelters depreciation claimed after May 6, 1997 — that recapture is always taxable, up to 25%. Second, gain attributable to periods of non-qualified use (generally, time the property was a rental after 2008 and before it became your home) is carved out of the exclusion on a pro-rata basis. For a property that went from home to long-term rental, the 2-of-5-year clock may have already run out, eliminating the exclusion entirely. Run the ownership and use timeline carefully before assuming any of the gain is excludable.
Frequently asked questions
What selling costs can I deduct from my taxable gain?
Real estate commissions, legal fees, title insurance paid by the seller, recording fees, transfer taxes, and other costs directly related to the sale reduce the amount realized and therefore the gain.
Does refinancing affect my taxable gain?
No. Taking cash out through a refinance is not a taxable event and does not change your basis or the gain at sale. Only capital improvements and depreciation change adjusted basis.
What if I sell at a loss?
A loss on a rental held for investment is deductible as a capital loss (or ordinary loss if sold to an unrelated party, depending on use), but passive activity loss rules may limit the deduction.
Do my suspended passive losses come off the gain?
Yes. When you fully dispose of a passive rental to an unrelated party, previously suspended passive losses from that activity are generally freed and can offset the gain and your other income. It is one of the most valuable and most overlooked benefits at sale.
Does paying off my mortgage at closing reduce my taxable gain?
No. Repaying loan principal is not a selling expense and does not affect your basis or gain. Your gain is based on sale price, selling costs, and adjusted basis — not on how much debt you carried.
Do I need to make an estimated tax payment after selling?
Usually. A large gain can far exceed your normal withholding, so make a quarterly estimated payment for the quarter the sale closes, or meet a safe harbor (90% of this year's tax, or 100%/110% of last year's), to avoid an underpayment penalty.
Which form do I use to report the sale of a rental?
Form 4797 is the primary form; it splits the ordinary recapture from the Section 1231 gain. The unrecaptured Section 1250 gain and long-term capital gain flow to Schedule D, with Form 6252 added for an installment sale or Form 8824 for a 1031 exchange.
Sources
- IRS Topic No. 409 — Capital Gains and Losses
- IRS Publication 544 — Sales and Other Dispositions of Assets
- IRS Publication 946 — How to Depreciate Property
Educational information and estimates only. Not tax advice. Tax rules change and vary by situation; consult a qualified tax professional before acting.