Overview
If you’re self-employed — operating as a sole proprietor or partner in a partnership — you can deduct a portion of your home expenses and vehicle costs from your business income under the Income Tax Act. These deductions reduce your net business income and therefore both your federal/provincial income tax and CPP premiums.
This is not a loophole in the exploitative sense — it’s an explicit statutory right under ITA s.18(12) (workspace-in-home) and ITA s.18(1)(a) (vehicle expenses). The key is knowing what qualifies, how to calculate it correctly, and how to document it.
Home Office Deduction (ITA s.18(12))
Who Qualifies
Your home workspace must meet one of two tests:
- Principal place of business — your home office is where you primarily conduct your business (most sole proprietors working from home qualify here), OR
- Exclusive use + client meetings — the space is used exclusively for business income-earning activity AND you use it regularly to meet clients, customers, or patients
Test 1 is the easier standard and covers most people running a business from home.
What You Can Deduct (Proportionally)
Calculate the business-use percentage of your home by dividing your workspace area by the total home area (e.g., 150 sq ft office ÷ 1,500 sq ft home = 10%).
Apply that percentage to eligible expenses:
- Rent (if you rent your home)
- Mortgage interest (not principal repayment)
- Property taxes
- Utilities (heat, hydro, water)
- Home insurance
- Maintenance and repairs attributable to the whole home
- Internet — typically 100% if used primarily for business, or prorated
What You Cannot Deduct
- Mortgage principal payments
- Capital improvements or renovations
- Personal portions of any expense
The Carry-Forward Rule
The home office deduction cannot create or increase a business loss. If your home expenses exceed your net business income, the excess is carried forward to the next year — it’s not lost, just deferred.
Example Calculation
| Expense | Annual Amount | Business % | Deductible |
|---|---|---|---|
| Mortgage interest | $18,000 | 10% | $1,800 |
| Property taxes | $5,000 | 10% | $500 |
| Utilities | $3,600 | 10% | $360 |
| Home insurance | $1,800 | 10% | $180 |
| Internet | $1,200 | 80% | $960 |
| Total | $3,800 |
At a 40% marginal tax rate, $3,800 in deductions saves roughly $1,520 in tax.
Vehicle Deduction (ITA s.18(1)(a))
What Qualifies
You can deduct the business-use percentage of your vehicle’s operating costs. Track your total kilometres driven and your business kilometres — the ratio is your deduction percentage.
Business kilometres include:
- Travel to client meetings, job sites, suppliers
- Travel between multiple business locations
- Picking up business supplies
Business kilometres do NOT include:
- Commuting from home to a fixed regular workplace (does not apply to most sole proprietors who work from home)
- Personal errands, family use
What You Can Deduct
- Fuel/gas
- Insurance
- Repairs and maintenance
- Lease payments (up to the prescribed annual limit — $1,050/month in 2024 for leases entered in 2024)
- Licence and registration
- Interest on a vehicle loan (up to $10/day for 2024)
- Capital Cost Allowance (depreciation) on a purchased vehicle (Class 10 or 10.1)
For purchased vehicles, the capital cost for CCA purposes is capped at $36,000 (2024) for passenger vehicles — costs above this threshold are not deductible.
Example Calculation
- Total kilometres driven in the year: 20,000 km
- Business kilometres: 12,000 km
- Business-use percentage: 60%
- Total vehicle operating costs: $8,000
- Deductible amount: $4,800
The Logbook Requirement
The CRA requires a logbook to support vehicle expense claims. Your logbook must record, for each business trip:
- Date
- Destination
- Business purpose
- Kilometres driven
A simplified logbook method is available if you maintained a full logbook for a base year: you can maintain a 3-month logbook in subsequent years and extrapolate the business-use percentage, provided it’s within 10% of the base year.
Documentation Best Practices
The CRA commonly audits home office and vehicle claims. Keep:
- Home office: Receipts for all home expenses, floor plans or measurements showing workspace area, lease/mortgage statements
- Vehicle: Mileage logbook (or app like MileIQ or TripLog), all fuel/repair receipts, insurance documents
Retain records for 6 years from the end of the tax year.
Where to Claim These Deductions
File Form T2125 (Statement of Business or Professional Activities) with your T1 personal return:
- Home expenses: Part 7 of T2125
- Vehicle expenses: Part 4 of T2125
Frequently Asked Questions
I work from my kitchen table, not a dedicated room. Can I still claim a home office deduction?
It’s difficult. The CRA generally expects your workspace to be a defined area used primarily for business, not a space shared with personal activities. A dedicated room that is used for business is the cleanest claim. A shared space like a kitchen or living room creates audit risk because the “exclusive or principal use” requirement is hard to satisfy for a multi-purpose space. If you work from a dedicated desk area but not an entirely separate room, a very conservative claim (small percentage of total home area) is defensible — but a CRA auditor may challenge it.
Can I deduct the full cost of a home renovation that includes my office?
No. Capital improvements (renovations that increase the value or extend the life of the property) are not deductible under the home office rules. You cannot claim any portion of a renovation unless it’s a minor repair. Renovations to your home are a personal capital expenditure. Exception: if the renovation is exclusively to your workspace (new flooring only in a dedicated office, for example), it may qualify as a repair/maintenance expense — but this is a gray area and should be discussed with your accountant.
My spouse also works from home in the same house. Can we both claim a home office deduction?
Potentially, but you cannot both claim the same square footage. If you each have separate workspaces, each person can claim their own workspace area as a proportion of total home area. If you share a workspace, it gets more complicated — only one person can claim each portion, and you’ll need to divide the square footage used between you.
What if I use my car for both my employed job and my self-employment business? Can I claim vehicle expenses for both?
You can only claim vehicle expenses for your self-employment business on Form T2125. If you’re also employed and your employer requires you to use your own vehicle for work, you would need a T2200 (Declaration of Conditions of Employment) from your employer and would claim those expenses separately on Form T777. The two claims cannot overlap — you can’t claim the same kilometres twice, and the total business-use percentage across both uses cannot exceed 100%.
Can I deduct my entire internet bill since I use it for business?
You can deduct the business-use portion. If you use internet primarily for business (many self-employed people do), a high percentage (70–100%) is supportable. However, if the same connection serves your household’s personal streaming, gaming, and family use, a CRA auditor may question a 100% deduction. A reasonable personal/business split based on actual usage is more defensible than claiming 100%.