US Stocks in Canada: A 10% Loss Can Still Be a Taxable Gain
Your brokerage account can show a US-listed stock down 10% while your Canadian tax return shows a gain on the same trade. The Canada Revenue Agency does not compute anything in US dollars: cost, proceeds and expenses each convert to Canadian dollars at their own date’s exchange rate. The Bank of Canada’s daily rate for the US dollar was 1.2040 on June 1, 2021, the series low, and 1.4002 on September 18, 2026, a currency 16.30% weaker than it was at that low.
That gap matters right now. We covered the 2026 tax-loss selling deadline this morning: the December 30 settlement date, what a harvested loss is worth, and the three-year carryback. This piece is the other half, because in Canadian dollars a US position may not be a loss at all.
Three legs, three dates, three rates
Section 261 of the Income Tax Act does not let a US-dollar gain translate directly: “if a particular amount that is relevant in computing those Canadian tax results is expressed in a currency other than Canadian currency, the particular amount is to be converted to an amount expressed in Canadian currency using the relevant spot rate for the day on which the particular amount arose”. Cost, proceeds and expenses arose on different days, so each gets its own rate.
The CRA Guide T4037, Capital Gains puts it in practical terms, on which values convert at which date: “the proceeds of disposition to Canadian dollars using the exchange rate in effect at the time of the sale; the ACB of the property to Canadian dollars using the exchange rate in effect at the time the property was acquired; the outlays and expenses to Canadian dollars using the exchange rate in effect at the time they were incurred”. The rate behind both is the Bank of Canada daily exchange rates series, FXUSDCAD, used throughout this piece.
The worked example: a 10% loss that owes tax
Take 200 shares of a US-listed stock, bought June 1, 2021 at USD $100.00, sold September 18, 2026 at USD $90.00, with a USD $4.95 commission each side.
On the brokerage screen, cost was $20,004.95 USD, proceeds were $17,995.05 USD: a loss of $2,009.90 USD, a 10.0% fall.
On Schedule 3, three different rates apply. The ACB converts at the June 1, 2021 rate of 1.2040: 200 x $100.00 x 1.2040, plus $4.95 x 1.2040, for a CAD ACB of $24,085.96. Proceeds convert at the September 18, 2026 rate of 1.4002: 200 x $90.00 x 1.4002, or $25,203.60. Outlays convert at their own date too: $4.95 x 1.4002, or $6.93. Net the ACB and outlays against proceeds and the position shows a capital gain of $1,110.71, half of which, $555.35, is taxable.
For an Ontario resident with $120,000 of taxable income, the marginal rate is 43.41%, putting the capital gains rate at 21.705%: tax owing on the “losing” position is $241.08.
Worked backward, the price would have had to fall to USD $85.99, a 14.01% drop from $100.00, before the Canadian-dollar result reaches zero.
The exchange rate effect, by the year you bought
The FX effect is not fixed at 16.30%: it depends on the Bank of Canada rate the day you bought, measured against the September 18, 2026 rate of 1.4002. The table below runs the first Bank of Canada quote of each calendar year since 2019.
| Bought | BoC rate | FX effect | USD price move needed to be flat in CAD |
|---|---|---|---|
| 2019-01-02 | 1.3600 | +2.96% | fall 2.87% |
| 2020-01-02 | 1.2992 | +7.77% | fall 7.21% |
| 2021-01-04 | 1.2751 | +9.81% | fall 8.93% |
| 2022-01-04 | 1.2708 | +10.18% | fall 9.24% |
| 2023-01-03 | 1.3658 | +2.52% | fall 2.46% |
| 2024-01-02 | 1.3316 | +5.15% | fall 4.90% |
| 2025-01-02 | 1.4418 | -2.89% | rise 2.97% |
| 2026-01-02 | 1.3737 | +1.93% | fall 1.89% |
Source: Bank of Canada series FXUSDCAD, first quote of each calendar year, against the September 18, 2026 quote of 1.4002.
Every year in the table works in the Canadian holder’s favour except one: anyone who bought at the first quote of 2025, when the dollar sat near its weakest point at 1.4418, needs the US price to rise 2.97% just to break even in Canadian dollars. The FX effect that year is -2.89%, the exception across 2019 through 2026, not the pattern.
The mirror image: FX cuts both ways
FX is not a one-way tool for the CRA. Run the same trade in reverse: 200 shares bought February 3, 2025, the series high of 1.4603, at USD $100.00, sold September 18, 2026 at USD $110.00. In US dollars that is a +10.0% gain, $2,000.00 USD; in Canadian dollars, ACB is $29,206.00, proceeds are $30,804.40, and the gain is $1,598.40, or +5.47%, roughly half the USD gain. A Canadian dollar that strengthens after purchase shrinks a USD gain the way a weakening one inflates a USD loss.
Two tranches: the ACB averages in Canadian dollars
Buy the same stock twice at different points in the FX cycle and the arithmetic stops being intuitive. 100 shares bought June 1, 2021 at USD $100.00 (rate 1.2040) cost $12,040.00 CAD. Another 100 shares bought February 3, 2025 at USD $100.00 (rate 1.4603) cost $14,603.00 CAD. The average USD cost per share is still $100.00, but the CAD adjusted cost base per share is $133.22: ACB is a running average of what was paid in Canadian dollars, not the US-dollar price. A USD-only spreadsheet cannot produce that number; it has to be rebuilt in CAD from each purchase’s own rate, which is what an adjusted cost base tracker is for.
The US dollars are their own property
Holding US dollars in a brokerage account is a capital property in its own right, separate from any shares bought with it. Selling USD back to CAD, or buying a different US stock with it, is a disposition of that currency. Section 39(1.1) of the Income Tax Act gives individuals a narrow floor on currency gains and losses: “A is the total of all the particular gains made by the individual in the year, B is the total of all the particular losses sustained by the individual in the year, and C is $200”.
Apply that to $20,000 USD acquired June 1, 2021 at 1.2040 and converted back to CAD on September 18, 2026 at 1.4002. The raw FX gain is $3,924.00. Subtract the $200 floor and the capital gain is $3,724.00, half of which, $1,862.00, is taxable. At the same 43.41% marginal rate, that is $808.29 of tax on currency movement alone, with no share ever changing hands.
The $200 floor is easy to misread as a general shelter. It applies only to dispositions of currency itself, not to the $1,110.71 share gain above; that is a separate property with its own calculation.
Practical notes
A few mechanics matter before filing. If a trade settles on a day the Bank of Canada does not publish a rate, the Act falls back on “the closest preceding day for which such a rate is quoted”.
The CRA’s Income Tax Folio S5-F4-C1 allows flexibility for recurring income, not a single disposition: “For practical reasons, the CRA may also accept the use of an average of exchange rates over a period of time in order to convert certain income items.” It then draws the line: “If exchange rates fluctuate significantly, the use of the average exchange rate for a period will not generally be accepted.” A share sale is not recurring income, so the day-of-transaction rate governs, not a yearly average.
Where a broker’s T5008 slip shows proceeds already converted to Canadian dollars, that conversion follows the broker’s own convention and is not CRA authority for your ACB. The three-rates rule above is what belongs on Schedule 3.
The exposure you didn’t choose
The exchange rate is a second position layered on every US stock a Canadian investor holds, one nobody chooses deliberately since it is simply the currency the shares are quoted in. There is a way to hold the same company without it: Tesla stock or the CAD-hedged CDR works through what a Canadian Depositary Receipt does and does not remove.
These figures use Ontario rates for a resident with $120,000 of taxable income; other provinces will produce different amounts. Data as of September 19, 2026; Bank of Canada quotes here are as of the September 18, 2026 fixing.
Before you file
Nothing here is tax or legal advice, and the arithmetic above is an illustration rather than a return. A US-dollar position held across several years, in tranches, with dividends reinvested, is exactly the case where a qualified tax professional earns their fee.
Disclaimer: The content on bestcanadianstocks.ca is for informational and entertainment purposes only and does not constitute financial advice. Past performance is not indicative of future results. Always consult a qualified financial advisor before making investment decisions. FX from the Bank of Canada daily exchange rate series for the US dollar, most recent quote September 18, 2026. Tax figures computed with the CRA’s 2026 federal and Ontario brackets and the Ontario surtax from CRA T4032ON, January 2026 edition. Rule citations from the Income Tax Act and CRA Guide T4037.
