Home Office Calculator

Business Use of Home

Form 8829 Calculator — Actual Expense Method — Tax Year 2025

Calculate your allowable deduction for business use of your home. This calculator follows the IRS Form 8829 line by line using the actual expense method. All calculations update in real time. Your entries are automatically saved to this browser.

First time here?

This calculator follows IRS Form 8829 line by line. Our guided walkthrough explains each field in plain English, tells you where to find each number, and gives you real examples. It takes about 5 minutes.

1
Area used regularly and exclusively for business, regularly for daycare, or for storage of inventory or product samples
sq ft
2
Total area of home
sq ft
3
Divide line 1 by line 2 (business percentage)
0.00%
7
Business percentage

Same as line 3

0.00%
8
Tentative profit or loss from Schedule C, line 29
$
(a) Direct
(b) Indirect
9
Casualty losses
$
$
10
Deductible mortgage interest
$
$
11
Real estate taxes
$
$
12
Add lines 9, 10, and 11
$0.00
$0.00
13
Multiply line 12, column (b), by line 7
$0.00
14
Add line 12, column (a), and line 13
$0.00
15
Subtract line 14 from line 8 (if zero or less, enter 0)

This is your deduction limit for operating expenses

$0.00

Operating Expenses

(a) Direct
(b) Indirect
16
Excess mortgage interest
$
$
17
Excess real estate taxes
$
$
18
Insurance
$
$
19
Rent
$
$
20
Repairs and maintenance
$
$
21
Utilities
$
$
22
Other expenses
$
$
23
Add lines 16 through 22
$0.00
$0.00
24
Multiply line 23, column (b), by line 7
$0.00
25
Carryover of prior year operating expenses
$
26
Add line 23 col (a), line 24, and line 25
$0.00
27
Allowable operating expenses (smaller of line 15 or line 26)
$0.00
28
Limit on excess casualty losses and depreciation (line 15 minus line 27)
$0.00

Excess Casualty Losses & Depreciation

29
Excess casualty losses
$
30
Depreciation of your home (from line 42 below)
$0.00
31
Carryover of prior year excess casualty losses and depreciation
$
32
Add lines 29 through 31
$0.00
33
Allowable excess casualty losses and depreciation (smaller of line 28 or line 32)
$0.00
34
Add lines 14, 27, and 33
$0.00
35
Casualty loss portion, if any, from lines 14 and 33

Carry amount to Form 4684

$0.00
36
Allowable expenses for business use of your home

Subtract line 35 from line 34. Enter on Schedule C, line 30.

$0.00

Method Comparison

Actual Expense vs. Simplified Method

Actual Method

Form 8829

$0.00

Personal expenses$0.00
Operating expenses$0.00
Depreciation$0.00

Simplified Method

$5 × sq ft (max 300)

$0.00

Business area0 sq ft
Rate$5.00 / sq ft
Max deduction$1,500.00

Enter your business area in Part I and your expenses in Part II to see which method gives you the larger deduction.

Key Differences

Max area
No limit vs. 300 sq ft
Depreciation
Yes vs. No
Carryover
Yes vs. No
Recordkeeping
Detailed vs. Minimal

Disclaimer: This calculator is provided for informational and educational purposes only. It is not a substitute for professional tax advice. The calculations follow the general structure of IRS Form 8829 but may not account for all special circumstances. Always consult a qualified tax professional and refer to the official IRS Form 8829 Instructions for your specific situation.

Business Use %

0.00%

Actual Method

$0.00

Simplified

$0.00