Filing season makes "doing your taxes" feel like one single task. It's really a handful of smaller pieces stacked together — here's what's actually in the stack.
The Four Parts of a Return
Income In
Everything you earned — employment, self-employment, investments, pensions, benefits — each reported on its own slip.
Deductions Applied
Amounts subtracted before tax is calculated — RRSP contributions, union dues, some employment expenses.
Credits Applied
Amounts that reduce the tax you owe directly — basic personal amount, tuition, medical expenses, donations.
The Result
Everything nets out to a refund or a balance owing, based on what was already withheld or paid during the year.
Slips People Forget
CRA usually already has a copy of every slip issued in your name — which is exactly why a missing one tends to surface later as a reassessment rather than a rejected return.
- T4 — employment income (rarely missed)
- T4A — pension income, self-employment commissions, scholarships, and more — easy to miss if it arrives separately from your T4
- T5 — investment income (interest, dividends)
- T3 — income from a trust or mutual fund
- T2202 — tuition, for students or a supporting parent
- RRSP contribution receipts — especially contributions made in the first 60 days of the new year
If You're Self-Employed
A few things change once self-employment income enters the picture:
- An extra form — the T2125 — reports your business income and expenses alongside your personal return
- Your filing deadline moves to June 15, but any balance owing is still due April 30 — interest starts accruing on that date even if you file on time
- Owing tax two years running can trigger quarterly tax installments the following year, which catches a lot of first-time self-employed filers off guard
Common Mistakes We See
- Missing a slip CRA already has on file — usually caught a few months later as a reassessment
- Not tracking receipts for credits and deductions until it's too late to find them
- Self-employed filers assuming the June 15 filing deadline also covers their balance owing
- Not checking whether next year's installments apply until the notice shows up