Home Office Calculator

What Your Home Office
Actually Deducts

Measure the space, enter the year's bills, and pick your situation. The work-space percentage, the bills the CRA lets you claim, and the deduction calculate instantly.

Greywood
Advisory

Home Office · 2026Deduction Calculator

01

Your Situation

Decides which bills count

02

Your Space

Square feet or metres, same for both
Length × width of the room, or a reasonable share of an open area
Every finished area counts, including hallways, bathrooms, and the kitchen
Work space as a share of your home Calculated: work space ÷ total area
0%
Months worked from home this year Only the bills for those months count
12
03

The Year's Bills

Full-year amounts; the months above prorate them
If you rent. Owners can't claim a rental value for the space
$
The year's hydro bills
$
Gas, oil, or propane
$
Water and sewer
$
The monthly access fee only, not connection charges or modem rental
$
Cleaning supplies, light bulbs, a furnace service call. Renovations are capital, not maintenance
$
Only the share your condo pays for heat, electricity, and water, if you don't pay those directly
$
The year's premium
$
Municipal and education, before any rebate
$
Interest only, never principal. Your annual mortgage statement has it
$
04

Income Limit

Optional
After your other employment expenses. The claim can't exceed it; the rest carries forward.
$
05

What It Saves

Optional
Where you'll file on December 31
Sets the rate the deduction saves at
$
Estimate
Home Office Deduction — 2026 · Salaried employee · Ontario
How it's built
Work space share of homeWork space ÷ total finished area
0%
Share of the weekA designated room counts in full
100%
Work use of the homeShare of home × share of the week
0%
Eligible billsThe full year, for the lines this situation allows
$0.00
Home office deduction
$0.00

Claimed on Form T777, then line 22900 of your return. Keep the signed T2200 with your records. Estimate only. Office supplies and work phone costs are claimed separately, and capital cost allowance on an owned home is left out on purpose: claiming it exposes part of your principal residence to capital gains when you sell. Confirm with your adviser before filing.

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About this estimate

The work-space percentage is the whole claim. Measure the room against every finished area of the home, including hallways, bathrooms, and the kitchen; a shared space is then claimed only for the hours it's actually used for work out of the 168 in a week. The rules are the same whether you're on a T4 or a T2125 — what changes is the list of bills. A salaried employee claims rent, utilities, internet, and minor repairs; commission income adds home insurance and property taxes; self-employment adds mortgage interest. Nobody claims mortgage principal, furniture, or renovations.

The claim can't exceed the income it relates to, so in a lean year the leftover carries forward rather than disappearing. If you're self-employed, our self-employed guide covers the home office alongside the vehicle claim, and the what to bring checklist lists the records that stand behind both. Employees need a signed T2200; our trades guide explains how to get one. To see the deduction's effect on your whole return, run it through the tax estimator.