Form 4684 – Casualties & Thefts

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Use the IRS Form 4684: Casualties and Thefts Tax Form Calculator IRS Form 4684: Casualties and Thefts as a stand alone tax form calculator to quickly calculate specific amounts for your 2026 4684 state tax return. Alternatively, you can use one of our Combined Federal and State Tax Estimators to quickly calculate your salary, tax, and take-home pay.

IRS Form 4684 is used by taxpayers to report gains or losses from property destroyed, damaged or stolen — whether for personal use or income‑producing property. The form distinguishes between personal‑use property and business or rental property, and importantly incorporates special disaster‑loss rules when the property loss is caused by a federally declared disaster. [IRS Instructions Form 4684 2024]

When to File Form 4684

You should complete Form 4684 if you experienced:

• Damage, destruction or theft of property used in your trade or business or rental activity;
• Damage, destruction or theft of personal‑use property in a federally declared disaster area; or
• A theft loss from a fraud or Ponzi scheme with special rules.

Note: For personal‑use property not connected with business, casualty and theft losses are generally deductible only if attributable to a federally declared disaster for tax years 2018‑2025. [IRS Topic 515]

Key Sections of the Form

• Section A – Personal‑Use Property: Report property not used for business or profit‑making purposes and apply the $100 (or $500 for qualified disasters) reduction and 10% AGI limitation.
• Section B – Business or Income‑Producing Property: Used for property in trade or business, or held for income, and does not require a disaster declaration to deduct.
• Section C – Theft‑Loss Deduction for Ponzi‑Type or Investment Schemes: Special rules apply when theft results from illegal investment schemes.
• Section D – Election to Deduct a Qualified Disaster Loss in the Prior Year: Allows taxpayers for certain disasters to deduct in the preceding tax year under election rules.

Important Calculation & Documentation Tips

• Include the cost or other basis of the property (Line 2) and subtract any insurance or reimbursement (Line 3).
• For personal‑use property, reduce by the $100 (or $500) per casualty and then by 10% of your adjusted gross income (AGI) unless it’s a qualified disaster event.
• For business property, separately calculate gain or loss depending on whether insurance or reimbursement exceeds basis.
• Collect and keep records of purchase dates, values before and after the event, FEMA disaster declaration numbers (if applicable), insurance claims, and repair estimates.

Using Form 4684 correctly helps you maximise legitimate deductions, comply with disaster‑loss rules, and avoid IRS delays or corrections. If you experienced significant property damage or theft, consult a tax professional for proper completion and filing.

Important Notes

All calculations are estimates for guidance only. Always review your return and consider professional advice when submitting official filings.