Last reviewed 25 August 2026 · Checked against CRA guidance · By the CryptoNorth Team
You can sell, but if you or an affiliated person rebuy the same coin within 30 days either side of the sale and still hold it on day 30, the loss is a superficial loss and cannot be claimed that year.[1]
The loss is not destroyed. It can usually be added to the cost base of the coin you bought back, so it reduces a future gain instead — that is the CRA’s own wording, and the “usually” is doing real work, because the add-back depends on who acquired the replacement property. Deferred rather than lost, which is the part most people get wrong.
A superficial loss requires both conditions to be true. One alone is not enough:
“You, or a person affiliated with you, buys, or has a right to buy, the same or identical property… during the period starting 30 calendar days before the sale and ending 30 calendar days after the sale”[1]
“You, or a person affiliated with you, still owns, or has a right to buy, the substituted property 30 calendar days after the sale”[1]
Note the window runs in both directions. A purchase made in the 30 days before you sell can trip the rule just as easily as one made after, which catches people who were dollar-cost averaging on the way down.
You hold 1 BTC with an adjusted cost base of $100,000 and decide to crystallise a loss before year end.
You cannot deduct the $30,000 against this year's gains. Instead the CRA lets you “add the amount of the superficial loss to the ACB of the substituted property”[1] — so the Bitcoin you bought at $72,000 now carries an adjusted cost base of $102,000.
Sell it later at $130,000 and your gain is $28,000 rather than $58,000. The relief arrives eventually; it just arrives in a different tax year than you planned.
What does not trip it: moving coins between wallets you control. That is not a disposition at all, so there is no loss to deny — see wallet transfers.
Tax-loss harvesting works in Canada, but the 30-day rule makes it a decision about market exposure rather than a free tax trick. You are choosing to be out of the asset for a month.
And if you do trip the rule, it is not a disaster. The loss follows your cost base forward. The people who get genuinely hurt are the ones who claim the loss anyway, because that is a filing error rather than a timing one.
The denied loss lands here — Canada uses average cost, not FIFO.
Yes, and a swap at a loss can trip the same 30-day rule.
No — not a disposition, so no loss to deny.
Only some apply the superficial loss rule automatically.
This page is general information, not tax advice. We are not accountants. It assumes you hold crypto as capital property; if your activity amounts to carrying on a business, losses are treated differently and the superficial loss rule does not apply in the same way. Whether a wrapped, staked or bridged token is “identical property” is unsettled. Speak to a CPA before acting on a large loss.
The full guide covers adjusted cost base, the 2026 rates, what counts as a disposition, and why exchanges do not yet report your trades to the CRA.
Read the full tax guide →