The most expensive deduction mistake Canadian landlords make is not claiming too much. It is claiming a capital cost as a repair.

A denied lunch costs you forty dollars. A $28,000 roof reclassified from Repairs to a depreciable building cost moves the deduction from one year to roughly twenty-five, and interest runs on the reassessment. This single line item is where audits on small portfolios usually land.

Here is the deductible list, the denied list, and the test separating a repair from an improvement.

The general rule

You deduct reasonable expenses incurred to earn rental income. Two words carry the weight.

Reasonable — priced at what an arm's-length party would charge. Paying your brother-in-law $9,000 to paint a one-bedroom fails.

To earn rental income — the expense exists because the property is rented. Costs from the period before the unit was available for rent, or during a stretch you used it yourself, are prorated out.

Deductible without argument

• Mortgage interest — the interest portion only, plus interest on a line of credit where the borrowed money went into the property. Loan setup fees, appraisal and mortgage broker fees are spread over five years at 20% a year.
• Property taxes for the rental period.
• Insurance premiums for the current year.
• Utilities the lease assigns to you.
• Condo fees — regular monthly contributions are deductible. A special assessment funding a structural project is capital.
• Advertising and tenant finder's fees.
• Property management and leasing commissions.
• Accounting, bookkeeping and rental software.
• Legal fees for lease preparation, rent collection and tenancy disputes.
• Repairs and maintenance meeting the current expense test below.
• Travel to collect rent and supervise repairs, excluding meals and lodging.
• Landscaping, snow removal, pest control, cleaning between tenancies.
• Salaries and the employer CPP and EI portions where you employ someone.

Denied, every year, without exception

The value of your own labour — you install the flooring yourself and save $3,000 in trades. Your deduction is the cost of the flooring. Zero for the weekend.

Land transfer tax — it goes into the adjusted cost base of the property and reduces your capital gain decades later. Never a current deduction.

Legal and other fees to purchase — same treatment. Into the cost base, allocated between land and building.

Mortgage principal — not an expense at any point.

Board and lodging while travelling for the property.

Two more worth naming: penalties and interest on late tax payments are not deductible, and interest on money borrowed for a personal purpose is not deductible even where the loan is secured by the rental. The CRA follows the use of the funds, not the collateral.

The current versus capital test

The CRA applies a handful of criteria. No single one decides it. You weigh them together.

• Lasting benefit — a cost delivering an enduring advantage is capital. Recurring costs restoring the property to working order are current. Repairing a section of shingles after a windstorm is current. Replacing the entire roof is capital.
• Maintenance or betterment — restoring the property to its original condition is current. Improving it past original condition is capital. Repainting the same walls is current. Replacing hollow-core doors with solid ones is capital.
• Part or whole — repairing an integral part of the building is current. Replacing a whole separate asset is capital. Fixing the compressor in an existing fridge is current. Buying a new fridge is capital, and lands in Class 8.
• Value relative to the property — a cost large in proportion to the property's value points toward capital.
• Timing around purchase — repairs made to a used property to bring it into serviceable condition after you buy it are capital, even where each individual job looks like a repair. This one catches the renovate-and-rent crowd hard. The gut job on the property you bought in March is not a March repair.
• Timing around sale — ordinary repairs before listing generally stay current. Work required as a condition of the sale, or done specifically to make the property saleable, is capital.

Two areas where landlords lose money quietly

Prorating a property with personal use — a duplex where you live in one side gets a reasonable split, usually by square footage. Line 9945 on the form removes the personal portion. Landlords who prorate by unit count instead of area, or who forget to prorate utilities at all, are creating a reassessment risk with no upside.

Vacant land — interest and property taxes on vacant land are limited to the income the land produces. They do not create a loss. Excess amounts get added to the land's cost base instead.

The documentation standard

The deduction survives if the paper survives. Keep records six years from the end of the tax year they relate to.

For each expense, you want the vendor invoice showing what was done and to which unit, proof of payment, and for anything over a few thousand dollars a short note on why it was current rather than capital. The note takes ninety seconds now and answers a question three years from now when nobody remembers the job.

Photographs help more than landlords expect. A before-and-after of a repair supports "restored to original condition" better than any invoice line reading "bathroom work."

The short version

Deduct anything reasonable keeping a rented property running. Capitalize anything making it better, bigger, or newly serviceable. Never deduct your own time, the principal, or the cost of buying the place.

The landlords who get this right are not smarter about tax law. They are the ones with a ledger forcing the decision at the moment of the expense, while they still remember what the contractor did.

In LuxOasisOS, every expense gets tagged to a unit and a T776 category as you enter it, with the receipt attached. Capital items route to a separate schedule instead of quietly inflating your repairs line.