Real Estate Tax Calc
The basic framework: proceeds vs. adjusted basis
When your rental property suffers a casualty — a fire, flood, storm, or other sudden event — and you file an insurance claim, the tax treatment depends on comparing the insurance proceeds to your adjusted basis in the damaged portion of the property.
If proceeds are less than your adjusted basis in the damaged portion: you have a casualty loss. For rental property, casualty losses are deductible on Form 4684 and Schedule E — rental property is business property, so the $100 and 10%-of-AGI floor that applies to personal property does not apply.
If proceeds are greater than your adjusted basis: you have a casualty gain. This gain is taxable unless you defer it under Section 1033 by reinvesting in replacement property.
How reinvesting the proceeds affects basis
If you receive insurance proceeds and spend the money on repairs that restore the property to its prior condition, the tax treatment is generally neutral: you deduct (or capitalize) the repair costs in the normal way, and your basis is roughly maintained.
If you receive proceeds and spend them on improvements that go beyond restoring the property — a bigger addition, a completely renovated kitchen where a simple one existed before — the improvement costs are capitalized and depreciated as a new asset. The basis of the improved portion reflects the new construction cost.
If you receive proceeds and do not reinvest in repairs (you keep the cash), and the proceeds exceeded your basis, you recognize the casualty gain in that year. That gain may be ordinary income or capital gain depending on how the property is classified.
Section 1033 deferral for rental casualty gains
Section 1033 allows you to defer a casualty gain (proceeds exceeding adjusted basis) by reinvesting in similar or related property within two years from the close of the first tax year in which any part of the gain is realized (three years for condemnation).
For a rental property casualty, 'similar or related in service or use' generally means another rental property used in the same way. To elect deferral, attach a statement to your tax return explaining the involuntary conversion, the amount realized, and how you reinvested the proceeds. Keep documentation of both the insurance claim and the replacement property purchase.
A worked example: partial fire damage with a gain
You own a rental building with an adjusted basis of $200,000 (original cost $260,000, less $60,000 of accumulated depreciation). A kitchen fire damages one unit. Your insurer pays $90,000 on the claim.
First, figure the basis in the damaged portion, not the whole building. Suppose the damaged unit represents 20% of the structure, so its allocated adjusted basis is roughly $40,000. The $90,000 of proceeds exceeds that $40,000 basis, producing a casualty gain of $50,000.
If you spend the full $90,000 rebuilding the unit to its prior condition, you can elect Section 1033 deferral: no gain is recognized now, and your basis in the rebuilt portion is its cost ($90,000) reduced by the $50,000 deferred gain — a carryover-basis mechanic that preserves the gain for a future sale. If instead you pocket $30,000 and spend only $60,000, the $30,000 not reinvested is taxable gain this year, and only the reinvested portion defers.
The mechanical point people miss: you compare proceeds to the basis of the damaged component, and even a partial insurance check can generate a taxable gain when a well-depreciated property has little basis left in the affected area.
Step by step: handling a rental casualty claim
1. Document the event and the date. The casualty must be sudden, unexpected, and identifiable. Photograph the damage, keep the fire or police report, and note the date — it starts the Section 1033 replacement clock.
2. Determine the adjusted basis of the damaged portion. Allocate original cost to the damaged component, add capitalized improvements to it, and subtract depreciation taken on it.
3. Total the insurance proceeds actually received for the casualty (net of any amounts for separate items like lost rents, which are ordinary income, not casualty proceeds).
4. Compare proceeds to basis to see whether you have a deductible loss or a taxable gain.
5. Decide whether to reinvest and elect deferral if there is a gain. File Form 4684 (casualties) and Form 4797 as needed, and attach the Section 1033 election statement if deferring.
6. Adjust your depreciation schedule. Restored or rebuilt property is a new asset placed in service on completion, with its own basis and recovery period.
Lost-rents and business-interruption proceeds are different
Insurance payments that reimburse you for lost rental income during repairs — business interruption or loss-of-rents coverage — are not casualty proceeds. They are a substitute for the rent you would have collected, so they are ordinary rental income reported on Schedule E in the year received. They do not enter the proceeds-versus-basis casualty calculation at all.
Keep the insurer's settlement breakdown. A single check often bundles structure damage (casualty proceeds), contents, and lost rents (ordinary income). Each piece is taxed differently, and you need the allocation to report correctly.
Common mistakes to avoid
Treating the whole check as tax-free. Proceeds above the damaged portion's basis are gain — a frequent surprise on older, heavily depreciated properties.
Applying the personal casualty rules. The $100-per-event and 10%-of-AGI floors, and the current-law limitation of personal casualty losses to federally declared disasters, apply to personal-use property. Rental property is business property, so a rental casualty loss is deductible without those floors and is not limited to declared-disaster events.
Missing the Section 1033 election or its deadline. The replacement period is generally two years from the close of the first year a gain is realized (three years for condemnation). Miss it and a deferred gain becomes taxable.
Deducting a rebuild that is really an improvement. Restoring to prior condition can often be expensed; a betterment or enlargement must be capitalized and depreciated. Getting this wrong distorts both the current deduction and future basis.
State tax angle
Most states that tax income conform to the federal treatment of casualty gains and losses on business property and to Section 1033 deferral, so a properly deferred federal gain is usually deferred at the state level too. But conformity is not universal — some states decouple from specific federal provisions or use a different date of conformity, and a few tax the gain in the year received regardless of a federal election.
If your rental is in a different state from your residence, the casualty gain is generally sourced to the state where the property sits, and you may have a nonresident filing obligation there. Confirm both the property state's and your home state's conformity before assuming the federal deferral carries through.
Timing: which tax year the gain or loss falls in
A casualty loss on business property is generally deductible in the year the casualty occurs, once the amount of the loss can be measured (reduced by any insurance reimbursement you reasonably expect to receive, even if the check arrives later). If you expect reimbursement and later receive less than expected, you deduct the shortfall in the year the claim is settled.
A casualty gain is realized when you receive proceeds that exceed the damaged property's adjusted basis. If your claim is still open at year end and you reasonably expect proceeds above basis but haven't received them, the gain is generally recognized in the year the reimbursement is received or reasonably certain — not necessarily the year of the fire or storm. This timing gap is why a casualty that happens in December can push the taxable event into the following year.
The Section 1033 replacement clock keys off the first year any part of the gain is realized, so pinning down that year precisely matters — it sets your deadline to reinvest and defer. Keep the insurer's payment dates and settlement correspondence to document exactly when the gain was realized.
Planning tips to minimize the tax hit
Reinvest fully and promptly. To defer the entire gain under Section 1033, reinvest an amount at least equal to the proceeds in qualifying replacement property within the replacement period. Reinvesting less exposes the shortfall to tax.
Separate the check into its components early. Ask the insurer for a settlement breakdown of structure, contents, and lost rents so each piece lands on the right line and in the right year.
Coordinate with depreciation. A rebuild placed in service is a fresh asset — a good moment to consider a cost segregation study on the reconstruction, which can accelerate depreciation on the new components.
Mind the recapture interaction. If proceeds exceed basis because the property was heavily depreciated, part of a recognized gain can carry ordinary-income recapture character. Model the character, not just the amount, before deciding whether to reinvest or pay the tax.
Frequently asked questions
Is insurance proceeds from a rental casualty taxable?
Only to the extent the proceeds exceed your adjusted basis in the damaged property. Below-basis proceeds result in a deductible loss; above-basis proceeds create taxable gain unless deferred under Section 1033.
How do I calculate the adjusted basis of the damaged portion?
Start with the original cost allocated to the damaged component, add any improvements, and subtract accumulated depreciation taken on that component.
What happens to my depreciation deduction in the year of the casualty?
You continue to take depreciation up to the date of the casualty. After the date of the event, depreciation on the damaged portion stops until repairs are complete and the asset is placed back in service.
Do the $100 and 10%-of-AGI casualty loss floors apply to my rental?
No. Those floors, and the current limitation to federally declared disasters, apply to personal-use property. A rental is business property, so its casualty loss is deductible on Form 4684 and flows to Schedule E without those limits.
Are business-interruption or lost-rent insurance proceeds taxable?
Yes, and separately from the casualty. Loss-of-rents proceeds replace rental income you would have earned, so they are ordinary income on Schedule E in the year received — they are not part of the proceeds-versus-basis casualty gain calculation.
How much time do I have to reinvest under Section 1033?
Generally two years from the close of the first tax year in which any part of the gain is realized (three years for a condemnation). You must reinvest in property similar or related in service or use and attach an election statement to your return.
Does rebuilding restore my depreciation to what it was?
Not exactly. The rebuilt or restored portion is treated as a new asset placed in service when work is complete, with its own basis and a fresh recovery period. Under Section 1033 deferral, that basis is reduced by any gain you deferred.
Sources
Educational information and estimates only. Not tax advice. Tax rules change and vary by situation; consult a qualified tax professional before acting.