Home Office Space: What Percentage of Your House Can You Claim?

The percentage of your home you can claim depends on how much of your living space is used exclusively for work. The Canada Revenue Agency (CRA) looks at the square footage of your dedicated home office divided by the total square footage of your home. For example, if your home office is 150 square feet and your entire home is 2,000 square feet, you could claim up to 7.5% of household expenses. The key rule: your home office space must be used regularly and exclusively for earning income to qualify under this rule. Your home office percentage determines how much you can deduct from shared household expenses. This is crucial because not every home expense can be split by square footage in the same way. Expenses that scale with your percentage: - Utilities (electricity, gas, water) - Property tax (if you own) - Home insurance - Mortgage interest or rent - Maintenance and repairs - Depreciation (if claiming capital cost allowance) Expenses that do NOT scale by percentage: - Internet and phone (only if exclusively for work) - Office supplies and equipment - Furniture purchased specifically for your office - Software subscriptions used only for work Use the Home Office

Frequently Asked Questions

Can I claim my whole home office percentage if I use the space for personal activities too?

No. The CRA requires exclusive use for earning income. If you use your office as a guest bedroom or entertainment space, you cannot claim that percentage. The space must be set up and used primarily for work.

Do I need to submit my square footage measurements and floor plan to the CRA?

You don't need to submit them upfront, but keep them in your records. If the CRA audits your claim, you'll need to provide proof that your percentage calculation is accurate and reasonable.

If my home office is 200 square feet and my house is 2,000 square feet, can I claim 10% of everything?

You can claim 10% of proportional expenses like utilities, property tax, and insurance. But office equipment, technology, and supplies used exclusively for work are claimed at 100%, not 10%.

What if I moved my home office partway through the year?

You need to calculate your percentage based on the actual months you used the space. If you set up your office in July, you claim expenses for July through December only, adjusted for your percentage during that period.

Is renting a separate office space better than claiming a home office percentage?

That depends on your tax situation and expenses. A separate office has higher rent costs but simpler deductions (100% of rent and utilities). A home office percentage spreads costs across shared expenses. Use the [Self-Employed Tax Estimator](/tools/self-employed-estimator) to compare both scenarios.

Steps

1. Measure your home office space: Use a tape measure to find the length and width of your dedicated work area in square feet. Be precise and include only the space used exclusively for earning income, such as walls, closets, and built-in shelving within that room.
2. Measure your total home space: Measure all rooms, hallways, closets, bathrooms, and storage areas in your home. You can estimate if exact measurements aren't available, but document your estimate method in case of an audit.
3. Calculate your percentage: Divide your office square footage by your total home square footage, then multiply by 100. For example, 150 / 2,000 × 100 = 7.5%. Round to one decimal place and keep this calculation with your records.
4. Identify proportional expenses: List household expenses that scale with your percentage: utilities, rent or mortgage interest, property tax, home insurance, maintenance, and repairs. Gather invoices and bills for the full tax year.
5. Calculate your deductible amounts: Multiply each proportional expense by your percentage. For example, if your annual heating bill is $2,000 and your percentage is 8%, you can claim $160 of heating costs.
6. Add 100% work-only expenses: List office equipment, furniture, supplies, and technology purchased exclusively for work. These are claimed at 100%, not your home office percentage. Keep receipts for items over $500.
7. Organize and file your records: Create a folder with your floor plan, measurements, percentage calculation, and all supporting invoices. Keep photos of your dedicated workspace. Store these records for at least six years in case the CRA requests documentation.