Keep the day trades out of the TFSA
The TFSA shelters investment returns, not businesses. When activity inside the account amounts to carrying on a securities-trading business, frequent fills, short holds, deep market knowledge, the account itself becomes taxable on that income, and the CRA has run a targeted review program on high-balance, high-turnover TFSAs for years. Both the Tax Court and the Federal Court of Appeal have upheld those assessments, and since 2019 the holder can be personally liable for the tax alongside the trustee.
The asymmetry most traders miss: the RRSP rules specifically carve out business income earned by trading qualified investments, and the TFSA rules do not. So placement is the plan. Patient positions, the compounding you actually want sheltered, belong in the TFSA; the scalps and swing setups belong in a non-registered account, where the activity can be a business without poisoning the shelter, and where margin interest is deductible, something no registered account offers.
A separate trap hides beside this one: a security that is not listed on a designated stock exchange, an over-the-counter penny stock, for instance, can be a non-qualified investment inside a TFSA or RRSP, carrying its own 50% tax on the holder. Speculative accounts should be screened for listing status before the ticket, not after.
Instalments assume the big year repeats
Clear more than $3,000 in net tax owing this year and in either of the two years before, and the CRA expects quarterly instalments on March 15, June 15, September 15 and December 15. The reminder letters use the no-calculation option, built from your last two returns, so in the spring after a windfall year the CRA bills the new year as if the windfall were permanent. You are allowed to pay on a different basis:
| Option | Computed from | When a trader picks it |
|---|---|---|
| No-calculation | The CRA reminders, from your last two returns | Steady years; no interest risk if paid as billed |
| Prior-year | Last year's tax alone | Last year was normal and the year before was the outlier |
| Current-year | Your estimate of this year's tax | The windfall is over; frees cash, but a low estimate accrues interest |
The current-year option is the release valve after a one-off year, and its risk sits entirely in the estimate: fall short and instalment interest runs at the prescribed rate, with a penalty stacked on once that interest passes $1,000. We reset the basis each quarter from actual trading results, not from January optimism.
A losing year can refund a winning one
Capital losses carry back up to three years on a Form T1A filed with the loss-year return, which turns a drawdown into a cheque against the tax you paid on the big year. The value is in the sequencing: realize the losses before year-end to claim the carryback this cycle, and keep re-entries outside the 30-day superficial-loss window, the records problem our trader accounting work tracks all year, or the loss is denied and migrates into the new position's cost base.
If your trading is business income rather than capital, the loss is more powerful still: deductible against employment or any other income, and carried as a non-capital loss if unused. But the character has to match the position taken in the profitable years. The one thing planning cannot do is switch you to business treatment retroactively because this year went badly.
The December file, and what a big year buys
Business-income traders build RRSP room, because trading profit on a T2125 is earned income, so a strong year funds a deduction that shelters part of itself. Capital-gain traders do not get that lever, which makes timing their main one: a gain realized in early January lands a full tax year later than one realized in late December, and a thin-income year, a sabbatical, a losing stretch elsewhere, is the cheap year for gains that were coming anyway. Remember that a security is disposed of on settlement, so the final trading days of December need checking against the calendar, not just the chart.
Each December we review the open superficial-loss windows, the instalment position and the account placement in one sitting. Tax Planning & Advisory runs on a written scope after a free 15-minute discovery call, and for solo traders who mostly need a fast answer between filings, an instalment reminder, a TFSA worry, a matching letter, CPA Quick Support at $99 a month covers the in-between. Our decisions library shows how we put calls like these in writing.
