Casualty & Theft Losses on Business Property (2026): The Form 4684 Deduction Freelancers Miss

Published: July 29, 2026 · Reading time: 11 min

TL;DR: The rule everyone repeats — "casualty losses are only deductible in a federally declared disaster" — is a personal tax rule. It has never applied to business property. If a flood, fire, theft, or burst pipe takes out equipment you use for work, you have a deduction. But it is capped by adjusted basis, not by what the thing was worth: if you already expensed that laptop under Section 179, its basis is $0 and so is your loss. And it doesn't go on a Schedule C line — it goes on Form 4684 → Form 4797 → Schedule 1.

Someone smashed the passenger window and took the camera bag off the back seat. Or the upstairs neighbour's washing machine hose let go over your home office. Either way, the first thing you'll read online is that casualty losses were basically abolished in 2018.

That is true, and it is about your sofa. It is not about your business.

The distinction that decides everything

Two different Internal Revenue Code subsections govern two different kinds of loss, and they have diverged sharply.

The Tax Cuts and Jobs Act suspended the personal casualty loss deduction outside federally declared disasters, and the One Big Beautiful Bill Act made that limitation permanent rather than letting it expire. Neither Act touched §165(c)(1). Business casualty and theft losses continue exactly as they always have.

So the question to answer first is never "was this a declared disaster?" It's "was this property used in my business, and how much?"

Mixed-use property splits

A laptop used 70% for client work and 30% for streaming is 70% business property. If it's stolen, you claim a business casualty loss on 70% of the adjusted basis and get nothing for the other 30% unless a federally declared disaster caused the loss. Keep the same business-use percentage you've been using for depreciation — inventing a more favourable one for the loss year is exactly the kind of inconsistency that draws attention.

What counts as a "casualty"

A casualty is damage or destruction from an event that is sudden, unexpected, or unusual. All three adjectives do work.

Theft has a legal definition

A theft loss requires the taking of property to have been illegal under the law of the state where it occurred, and to have been done with criminal intent. Burglary, robbery, larceny, and embezzlement all qualify. So does fraud in many circumstances.

Two practical consequences follow:

1. File the police report. It's the cheapest possible contemporaneous evidence, and its absence is the first thing an examiner will notice.
2. The loss belongs to the year you discovered it, not the year the property disappeared. An embezzling bookkeeper who's been at it for three years produces one deduction, in the year you found out.

Computing the loss: basis is the ceiling

This is where most freelancers discover their deduction is smaller than they expected — sometimes zero.

For property completely destroyed or stolen:

Loss = Adjusted basis − salvage value − insurance or other reimbursement

The fair market value of the property is not part of this calculation for a total loss of business property. It doesn't matter that the camera would have sold for $2,000 on the used market.

For property partially damaged:

Loss = lesser of (adjusted basis, decrease in FMV) − insurance or other reimbursement

The decrease in FMV is usually established by a repair estimate or an appraisal. Actual repair cost is acceptable evidence when the repairs restore the property to its pre-casualty condition and aren't excessive.

Adjusted basis, and why yours is probably tiny

Adjusted basis is what you paid, plus capital improvements, minus every deduction you have already taken against the property's cost:

• Section 179 expensing
• Bonus depreciation — currently 100%, permanently restored by the OBBBA for property placed in service after January 19, 2025
• Regular MACRS depreciation
• The de minimis safe harbor election

Notice what those four have in common. Each of them accelerates your write-off. Each of them therefore destroys your casualty deduction on the same property.

This is not a penalty. A $0 casualty deduction on a fully expensed laptop is the correct answer, because you already deducted 100% of that laptop. Taking the loss too would be deducting it twice. The point of understanding it is to stop you expecting a windfall that isn't coming — and to stop you claiming one.

Worked example: Jordan's flooded home studio

Jordan is a freelance photographer in a rented ground-floor apartment with a dedicated studio room used 100% for business. In March 2026, the upstairs unit's water heater fails overnight and the studio is destroyed. The county is never declared a disaster area.

All four assets were placed in service in 2024, so two years of MACRS have run: 52% claimed on 5-year property (20% + 32%) and 38.78% on 7-year furniture (14.29% + 24.49%), under the half-year convention.

At a 22% marginal federal income tax rate that's about $714. Note the rate: this deduction reduces income tax only, not self-employment tax — see where it lands on the return, below.

Three things in that table are worth sitting with.

The camera was the most valuable item and produced nothing. $3,400 of gear, $0 of deduction, because Jordan took the whole thing under §179 two years earlier. He got the money then.

The denied insurance claim is what made the workstation deductible in full. You reduce the loss by reimbursement received or reasonably expected, not by the cheque that has actually cleared — so a claim still pending at filing time gets subtracted at your best estimate and trued up later. (§165(h)(4)(E) goes further for personal-use property and denies the deduction outright if you never file a timely claim; for business property the reduction is driven by what is genuinely recoverable.) Either way, a denial letter is the cleanest possible proof that the recoverable amount is zero. Keep them.

Nothing here reduces Jordan's Schedule C net profit, so nothing here reduces his self-employment tax. The $3,244 lands on Schedule 1 and reduces income tax only. That's a real difference — the same $3,244 as an ordinary business expense would also have cut self-employment tax at roughly 14 cents on the dollar, worth about $450 more.

Where it actually goes on the return

The routing surprises people who expect a Schedule C line.

1. Form 4684, Section B — "Business and Income-Producing Property." Section A is the personal one; do not use it.
2. Form 4797 — Sales of Business Property. Casualty losses on business property are treated as dispositions.
3. Schedule 1 (Form 1040), then to Form 1040.

There is no Schedule C line for a casualty loss. Not Line 21, not Line 27a. Putting it there overstates your business deductions, understates your net profit on Line 31, and wrongly reduces your self-employment tax — which is a real understatement of tax, not a harmless misclassification.

What is still a Schedule C expense

That distinction — restore it on Line 21, replace it on Form 4562 — is the one that most often gets miscoded, and it's worth getting right because a repair is deductible now while a replacement is depreciated.

When insurance turns a loss into a gain

Insurance settlements are based on replacement cost or actual cash value. Your basis is based on what you paid minus what you've deducted. Those two numbers drift apart fast, and the settlement frequently wins.

Example. Jordan's lighting kit had an adjusted basis of $1,200. Suppose the insurer had settled on replacement-cost terms and paid $2,000 instead of $700.

• Proceeds $2,000 − basis $1,200 = $800 gain
• §1245 recapture is the lesser of the gain ($800) or the depreciation already claimed ($1,300) — so the entire $800 is ordinary income, not capital gain

A cheque that felt like being made whole is a taxable event.

Section 1033 lets you defer it

An involuntary conversion — casualty, theft, condemnation — qualifies for deferral under §1033 if you reinvest in similar or related-in-service-or-use property.

Buying a better camera with the insurance money is the natural instinct anyway. §1033 just requires you to say so on the return, in writing, in the right year. Miss the election and the gain is simply taxable.

Federally declared disasters: the one place the rules converge

If your loss does occur in a federally declared disaster area, business owners get an extra option that has nothing to do with the personal-property restriction.

Under §165(i), you may elect to claim a disaster loss on the prior year's return — by amending it — instead of the year of the loss. That pulls the refund forward by roughly a year, which is precisely when a business that just burned down needs cash.

Whether it's the better answer depends on your marginal rate in each year. A high-income prior year makes the election attractive; a prior year at a low rate does not. Model both. The election has a deadline tied to the due date of the following year's return, so it is not a decision you can defer indefinitely.

The four records that make or break the claim

Most denied casualty deductions fail on evidence, not on law. And they nearly always fail on the first item below, because it's the only one you have to have created before the loss.

Without the first one, there is no deduction to compute. The Cohan rule gives a court discretion to estimate some expenses on imperfect records, but it is a fallback with a hostile audience, not a filing strategy — and it has never been a substitute for a basis figure.

This is the practical argument for keeping purchase receipts long past the point where the asset feels current. The receipt for a five-year-old monitor is worthless right up until the day the studio floods.

One more habit worth building: photograph your workspace once a year. Wide shots of the desk, the shelves, the gear cabinet. It takes ninety seconds, it timestamps itself, and after a fire it is the only proof that the things you're claiming existed at all.

Quick reference

Frequently Asked Questions

Can I deduct a stolen laptop on Schedule C?

You can deduct a theft loss on business property, but not on a Schedule C expense line and rarely for what the laptop is worth. It goes on Form 4684 Section B, flows to Form 4797, and lands on Schedule 1 rather than reducing Schedule C net profit. The deduction equals adjusted basis minus insurance reimbursement — not replacement cost, not fair market value. If you already expensed the laptop under Section 179, bonus depreciation, or the de minimis safe harbor, its basis is zero and so is the deduction, because you already deducted the entire cost in an earlier year.

Does the federally declared disaster rule apply to business property?

No, and it's the most misunderstood point in this area. The Tax Cuts and Jobs Act suspended personal casualty losses outside federally declared disasters and the One Big Beautiful Bill Act made that permanent, but that restriction sits in §165(h) and reaches only personal-use property. Losses on property used in a trade or business fall under §165(c)(1) and were never suspended. A burst pipe destroying your business computer is deductible regardless of any disaster declaration; the same pipe destroying your living-room television generally isn't.

How much is a business casualty loss worth?

For property completely destroyed or stolen, the loss is adjusted basis minus salvage minus insurance — the decline in fair market value is irrelevant. For partially damaged property it's the lesser of adjusted basis or the decrease in fair market value, again net of reimbursement. Adjusted basis is cost plus improvements minus all depreciation, Section 179, and bonus depreciation already claimed. The $100 per-event floor and the 10%-of-AGI threshold that gut personal casualty deductions don't apply to business property at all.

What if insurance pays me more than the property was worth on my books?

Then you have a taxable gain rather than a loss. Insurance of $4,000 on equipment with a $1,500 adjusted basis produces a $2,500 gain, and to the extent it reflects depreciation you already deducted it's recaptured as ordinary income under §1245. You can defer it under §1033 by buying qualifying replacement property within the replacement period — generally two years from the end of the first tax year in which any gain is realized — and electing deferral on the return. Reinvest at least the full proceeds and the whole gain defers; reinvest less and the shortfall is taxed.

What records do I need to prove a casualty or theft loss?

Four, and the first is the one people lack. Proof of adjusted basis — original receipt plus depreciation schedule — because without a basis figure there's no computable deduction. Proof the event happened: police report, insurance claim, dated photographs, a contractor's estimate, a weather or utility record. The reimbursement documentation, including any denial letter. And evidence of business-use percentage, since mixed-use property is deductible only in proportion. Theft losses are claimed in the year of discovery, so record that date too.

Authoritative References

• IRS — Publication 547, Casualties, Disasters, and Thefts
• IRS — About Form 4684, Casualties and Thefts
• IRS — About Form 4797, Sales of Business Property
• IRS — Publication 946, How To Depreciate Property
• IRS — Publication 535, Business Expenses
• IRS — Disaster Assistance and Emergency Relief for Individuals and Businesses

The Deduction Depends on a Receipt You Bought Years Ago

Every casualty claim comes down to one number you cannot reconstruct after the fact: what you paid, and what you've already written off. That's a filing problem long before it's a disaster problem. CentSense keeps the purchase receipt for every asset scanned, dated, and categorized to the right Schedule C line, so the basis history is there when a claim needs it — years later, from any device, even if the shoebox went under water with everything else. Start free with 10 AI scans a month, no credit card; the Solo plan ($5/month) adds unlimited scanning and mileage tracking.

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This article is educational and not tax advice. Casualty and theft loss treatment, basis computation, and §1033 elections are fact-specific. Consult a qualified tax professional about your situation.