Independent form guide. BrieflyGo is not affiliated with or endorsed by IRS, USCIS, SSA, DOL, or any U.S. government agency. Official forms are sourced from public government websites.
Official form guide
Form 4684: Casualties and Thefts
IRS Form 4684 is used to report gains and losses from casualties and thefts. Taxpayers must attach it to their return and, for a 2025 disaster loss, elect by October 15, 2026 (6 months after the regular due date).
Need help with Form 4684?
Open it in the AI Editor for field guidance, checks, and PDF export.
Need help? AI Editor guides you through every field of Form 4684.
Start filling →Form Overview
IRS Form 4684 - Casualties and Thefts
IRS Form 4684 is used to report gains and losses from casualties and thefts. Taxpayers must attach it to their return and, for a 2025 disaster loss, elect by October 15, 2026 (6 months after the regular due date).
Risk Radar
Scan points- 1Missing the Oct 15, 2026 election deadline eliminates the disaster loss deduction.
- 2Failing to make the disaster‑loss election by October 15, 2026 forfeits the deduction.
- 3Omitting Part B, lines 20‑27 for each lost item.
- 4Not attaching additional sheets when more than four items are listed.
- 5Incorrectly allocating amounts between lines 29 and 34.
Plain English
Form 4684 tells the IRS how much you lost or gained from a fire, flood, theft, or other casualty. You list each item, total the loss, and attach the form to your tax return. The form also lets you claim a special disaster‑loss election if you qualify.
Submission Date
- Filing date: 2026-01-23 15:10:36
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
AI co-pilot
Fill it faster. Catch mistakes before you file.
What this form is for
- Use this form when reporting gains or losses from casualties, thefts, or qualified disaster losses.
- Do not use it when reporting a casualty or theft of Section 179 property of a partnership or S corporation.
- Check Form 4797 instead when reporting a casualty or theft of Section 179 property of a partnership or S corporation.
Form selector
Use this form or another form?
Need to amend deductions due to casualty loss
Adjusted deductions must reflect the loss calculated on Form 4684
✓ Verify loss figures on Form 4684 match the attachment
Casualty loss involves home used for business on Schedule C
Business‑use home deduction is calculated on Form 8829 and transferred to Form 4684 line 27
✓ Ensure Form 8829 line 35 amount is entered on Form 4684 line 27 with “See Form 8829”
Casualty or theft of Section 179 property by partnership or S corporation
Section 179 transactions are reported on Form 4797, not Form 4684
✓ Confirm partnership/S corp filed Form 4797 and referenced on Schedule K‑1
Deadline or filing window
The filing trigger is a casualty or theft loss that qualifies as a federally declared disaster. To deduct a 2025 disaster loss on the 2024 return, the election must be made by October 15, 2026, which is six months after the regular due date for the 2024 return. No extension is mentioned for this election deadline.
Checklist
What you need before filling it out
Section B, lines 19‑26
Details of casualty or theft loss for home used in business or rented · Instructions p.10
Line 27
Deductible loss amount from Form 8829 or attached statement · Instructions p.10
Lump‑sum reimbursement allocation
Fair market values of each asset at loss time · Instructions p.7
Section C, line 20
Name, taxpayer identification number, and address of fraudulent arrangement party · Instructions p.10
Section A for simplified home office method
Casualty loss calculated using simplified method · Instructions p.10
Before you submit
- 1Verify the revision date on the form reads 20/25
- 2Confirm the loss qualifies as a casualty, theft, or qualified disaster loss
- 3Complete Section A for personal property losses
- 4If the loss involves a business or rental home, fill Section B lines 19‑26
- 5Allocate lump‑sum reimbursements based on fair market value at loss time
- 6Attach required statements such as Form 8829 reference or reimbursement allocation
- 7Sign the form where indicated
- 8Attach Form 4684 to your tax return
- 9Retain a copy of the completed Form 4684 for your records
How to file this form
- 1Determine whether the loss qualifies as a casualty, theft, or qualified disaster loss
- 2Complete the appropriate sections of Form 4684 (Section A, B, or C) with required calculations
- 3Attach supporting documents such as Form 8829, allocation statements, or other reimbursements
- 4Sign the form and attach it to your tax return before filing
- 5Submit the return to the IRS and keep a copy of Form 4684 for your records
Known limitations
- 1Partnerships or S corporations with Section 179 property must not use Form 4684; they must report the transaction on Form 4797 (Instructions p.10).
- 2Casualty or theft gains from trade, business, or income‑producing property held more than one year must be reported on Form 4797, not on Form 4684 (Instructions p.12).
- 3Only one Form 4684 may be used for lines 13 through 18; additional forms for those lines are not permitted (Form p.1 caution).
Field map
Compact field-by-field guide
General Info
2 items
Full legal name and taxpayer identification number (SSN or EIN).
Current mailing address.
Details
2 items
Complete all applicable sections of this form according to the official IRS instructions.
Enter the relevant dollar amount if this form involves tax calculation.
Certification
1 items
Read and acknowledge any certifications required by this form.
Signatures
1 items
Sign and date. Unsigned forms cannot be processed.
Almost done reviewing the fields?
Fillable formOpen in Editor->The edition is dated 20/25; the instructions point to IRS.gov/Form4684 for the latest information. The filing relief for natural disasters act expanded mandatory postponement of certain tax deadlines for disasters declared after July 24, 2025.
What changed or needs a fresh check
- Edition date — confirm the revision reads 20/25
- Fee — Not stated in the official source
- Mailing address — Not stated in the official source
- Signature — Not stated in the official source
Quick Facts
Downloads
After you file
- 1Retain a copy of the filed Form 4684 and all supporting documents for at least three years.
- 2If the loss makes itemizing advantageous, attach Schedule A (Form 1040 or 1040‑NR) with the filed Form 4684 (Instructions p.1).
- 3Complete Form 1040‑X to recalculate tax and claim any refund resulting from the casualty loss (Instructions p.1).
- 4Access Form 1040‑X at IRS.gov/Form1040X for future amendments (Instructions p.1).
- 5Keep the amendment, the corrected Form 4684, and any related schedules for the record‑retention period.
- 6If an error is discovered, file an amended return using Form 1040‑X and include a corrected Form 4684.
Sources
- SRCInstructions p.1 — attach Schedule A (Form 1040 or 1040‑NR) and Form 4684 to an amended return when itemizing.
- SRCInstructions p.1 — complete Form 1040‑X to refigure tax and claim a refund.
- SRCInstructions p.1 — Form 1040‑X is available at IRS.gov/Form1040X.
- SRCInstructions p.1 — prior revisions of Form 4684 are available at IRS.gov/Form4684.
- SRCInstructions p.8 — enter $500 on line 11 if line 10 is larger; otherwise enter $100.
- SRCInstructions p.9 — when filing Schedule A only to claim an increased standard deduction due to a disaster loss, enter zero on Form 6251 line 2a and include the pre‑increase standard deduction amount.
- SRCInstructions p.10 — partnerships and S corporations with Section 179 property must not use Form 4684; use Form 4797.
- SRCInstructions p.12 — casualty or theft gain from property held >1 year must be reported on Form 4797, not Form 4684.
Common confusion points
Do I need to file Form 4684 if I didn’t itemize deductions originally?
The instructions require determining whether the loss now makes itemizing advantageous.
→ Compare total casualty loss plus other itemized deductions to your standard deduction.
What amount should I enter on line 11 for a qualified disaster loss?
Line 11 depends on whether line 10 is larger or smaller.
→ If line 10 is larger, enter $500; otherwise enter $100 (Instructions p.8).
Can a partnership use Form 4684 for Section 179 property?
Partnerships and S corporations with Section 179 property are instructed not to use Form 4684.
→ Verify the entity type and property classification; use Form 4797 instead (Instructions p.10).
Should a casualty gain from property held over one year go on Form 4684?
Gains on property held more than one year must be reported on Form 4797, not Form 4684.
→ Check the holding period; if >1 year, complete Form 4797 Part III and skip Form 4684 line 34 (Instructions p.12).
Do I file Schedule A just to claim an increased standard deduction due to a disaster loss?
The instructions direct a zero entry on Form 6251 line 2a and inclusion of the pre‑increase standard deduction amount.
→ Follow the zero‑entry rule on Form 6251 and use the standard deduction amount from Schedule A (Instructions p.9).
How many Form 4684 can I use for lines 13‑18?
A caution note states only one Form 4684 may be used for those lines.
→ Ensure only a single Form 4684 is attached for lines 13‑18.
Workflow map
Related forms and next steps
Before
Current
After
Often used with
⚠ If something goes wrong
- Form 4797 – report casualty or theft gain from business property held >1 year instead of Form 4684.
- Form 6251 – adjust standard deduction when filing Schedule A solely for a disaster‑related increase.
Questions about IRS Form 4684
What is IRS Form 4684 used for?
Form 4684 tells the IRS how much you lost or gained from a fire, flood, theft, or other casualty. You list each item, total the loss, and attach the form to your tax return. The form also lets you claim a special disaster‑loss election if you qualify.
Who must file IRS Form 4684?
Individuals, estates, trusts, and businesses that incurred casualty or theft losses must file IRS Form 4684.
What information does IRS Form 4684 require?
The form collects details of each loss on Part B, lines 20‑27, a summary on line 28, and allocates short‑ and long‑term amounts on lines 29‑34. Additional sheets are required if more than four items are listed.
When is IRS Form 4684 due?
For a 2025 disaster loss, the election must be made on or before October 15, 2026, which is six months after the regular due date of the 2024 return.
How do I complete IRS Form 4684?
First, list each casualty or theft item on Part B, lines 20‑27, using a separate line for each loss. If more than four items are lost, attach additional sheets that follow the same format. Next, total the losses on line 28 and allocate the amount between short‑term (line 29) and long‑term (line 34) holdings. Attach the completed Form 4684 to your tax return, and if revoking a prior election, include Section D with an amended return.
Do I need to file Form 4684 if I didn’t itemize deductions originally?
The instructions require determining whether the loss now makes itemizing advantageous. Compare total casualty loss plus other itemized deductions to your standard deduction.
What amount should I enter on line 11 for a qualified disaster loss?
Line 11 depends on whether line 10 is larger or smaller. If line 10 is larger, enter $500; otherwise enter $100 (Instructions p.8).
Can a partnership use Form 4684 for Section 179 property?
Partnerships and S corporations with Section 179 property are instructed not to use Form 4684. Verify the entity type and property classification; use Form 4797 instead (Instructions p.10).
Source transparency
Copyright & Licensing - US Government Forms
BrieflyGo links to and explains official public form sources. We are not a government agency, and this page is for general form guidance, not legal advice.
Understand the agreement before you sign it.
Review risky clauses in plain English, fix the document, and keep it moving toward signature.