What are home office casualty losses?
If your home office was damaged in 2025 by a casualty or theft (for example, hurricane, tornado, fire, theft or vandalism) you may qualify for a business deduction. Casualty losses can be entered on the Expenses for the Entire Home or Home Office Only Expenses screens, depending on if they were for the entire home or only the home office.
Casualty losses entered on the Expenses for the Entire Home screen will be multiplied by your business use percentage. For example, a storm damages your roof. Since the roof is part of the whole house and used for both business and personal purposes, only part of it is considered a business expense. You would enter the amount you calculated on Line 15 and Line 18 of Form 4684 and we'll prorate the business portion of your casualty loss.
If you're taking the standard deduction without increasing it by a disaster loss, enter all casualty losses as excess casualty losses.
If you're itemizing deductions on Schedule A or taking the standard deduction and increasing it by a casualty loss to calculate your indirect casualty loss:
Casualty losses entered on the Expenses for the Entire Home screen will be multiplied by your business use percentage. For example, a storm damages your roof. Since the roof is part of the whole house and used for both business and personal purposes, only part of it is considered a business expense. You would enter the amount you calculated on Line 15 and Line 18 of Form 4684 and we'll prorate the business portion of your casualty loss.
If you're taking the standard deduction without increasing it by a disaster loss, enter all casualty losses as excess casualty losses.
If you're itemizing deductions on Schedule A or taking the standard deduction and increasing it by a casualty loss to calculate your indirect casualty loss:
- Treat all casualty losses as personal expenses.
- Use Form 4684 to calculate your casualty losses related to your home.
- Enter the amount from Line 15 and Line 18 of Form 4684 as an expense on the Expenses for the Entire Home screen. (Only include Line 15 if using a standard deduction increased by a casualty loss)
- Keep this form with your records but don't file it with your return.
