File T2125 with Proper Categories

Your self-employed tax return must report business income on Schedule T2125 of your T1 return with revenue and expenses classified under the correct CRA line codes. Misclassifying contractor income or lumping all expenses into a single category triggers CRA review letters and delays your self-employed tax refund processing.

Claim the Home Office Deduction

If you use a dedicated workspace for your self-employed business, calculate the square footage percentage and deduct that portion of rent, utilities, insurance, and internet on your contractor tax return. CRA requires the ITA section 18(12) workspace test to be met — either principal place of business or used exclusively to earn self-employed income.

Track Vehicle Expenses with a Mileage Log

CRA requires a mileage log to support vehicle expense deductions on your self-employed tax return. Record every business trip with date, destination, purpose, and kilometres. Without this log, CRA denies the entire vehicle deduction on your contractor tax return — fuel, insurance, maintenance, and CCA on the vehicle are all lost.

Plan Quarterly Instalment Payments

If your self-employed net tax owing exceeds $3,000 in the current or either of the two prior years, CRA requires quarterly instalments due March 15, June 15, September 15, and December 15. Missing self-employed instalment deadlines triggers interest at the prescribed rate compounded daily — proper planning on your contractor tax return avoids this cost.

Maximize CPP Contribution Strategy

Self-employed individuals pay both the employee and employer portions of CPP on their contractor tax return — double what salaried workers pay. If your self-employed net income exceeds the annual maximum pensionable earnings, you cap out. Below that threshold, every dollar of net self-employed income increases your CPP cost, so deduction planning directly reduces this obligation.

Deduct Professional Development Costs

Courses, certifications, conferences, and professional memberships directly related to your self-employed work are deductible on your contractor tax return under T2125. Many self-employed professionals miss these deductions because receipts are not tracked separately. Each missed deduction increases your self-employed taxable income unnecessarily.

Write Off Bad Debts Properly

If a client refuses to pay an invoice you already reported as self-employed income, you can deduct the bad debt on your contractor tax return under ITA section 20(1)(p). The key is documenting your collection efforts. Unclaimed bad debts mean you pay tax on self-employed income you never actually received.

Register for HST Voluntarily

Even if your self-employed revenue is under $30,000, voluntary HST registration lets you recover ITCs on all business expenses — equipment, software, supplies — on your contractor GST/HST return. For self-employed professionals with significant startup costs, this turns HST paid on expenses into a cash refund before you reach the mandatory registration threshold.

Evaluate Incorporation Timing

If your self-employed net income on T2125 consistently exceeds $80,000, incorporating and filing a T2 corporate tax return instead of a personal contractor tax return can save $10,000 or more annually through the Small Business Deduction rate of 12.2% versus the top personal marginal rate on self-employed income.

File on Time to Avoid Penalties

Self-employed individuals have until June 15 to file their contractor tax return, but any tax owing is still due April 30. Late self-employed tax filing triggers a 5% penalty on the unpaid balance plus 1% per month for up to 12 months. Filing your self-employed return on time with a payment plan avoids these penalties entirely.