How Do Capital Loss Carryforwards Work?
A net capital loss can be carried back three years to recover tax already paid on capital gains, or forward indefinitely against future gains. It cannot be applied against salary, pension or interest income, which is the constraint that surprises people.
- The answer:: Losses first offset gains in the same year; any excess carries back three years or forward indefinitely against capital gains.
- The trap:: Expecting a loss to reduce ordinary income. Outside the year of death it cannot, no matter how large the loss is.
- The recommendation:: Check the three prior years before carrying forward, because a carryback recovers tax already paid rather than waiting for a future gain.
Where the AI summary above gets this wrong
"You can deduct up to $3,000 of capital losses against your income each year."
That's surface-true. Here's what it misses:
- That is a United States rule — Canada has no annual allowance against ordinary income. Capital losses offset capital gains and nothing else.
- The carryback is worth checking first — Three years back recovers tax already paid, which is cash now rather than a deduction against a gain that may never occur.
- Death is the exception — On a final return, unused net capital losses can be applied against other income, subject to a reduction for capital gains exemptions previously claimed.
01 Where a loss can go
Capital losses first reduce capital gains in the same year. If losses exceed gains, the excess becomes a net capital loss, which can be carried back against the three preceding taxation years or carried forward indefinitely.
In every one of those years it offsets capital gains only. There is no annual allowance against employment, pension or interest income; the widely quoted three thousand dollar figure is a United States provision with no Canadian equivalent.
Source: Capital gains (line 12700)
02 Why the carryback usually comes first
A carryback amends a prior return and produces a refund of tax already paid. A carryforward is a deduction against a gain that has not happened yet and may not happen for years.
Checking the three prior years before filing is therefore worth the few minutes it takes. Where gains were realised in any of them — a property sale, a portfolio rebalance — the loss converts directly into cash.
Shows: what a given amount of additional taxable income costs you in tax at your marginal rate, and what you keep. Ignores: provincial surtaxes, credits that phase out with income, and any effect on income-tested benefits.
Source: Capital gains (line 12700)
03 The exception at death
On a final return, net capital losses that remain unused can be applied against income of any kind, reduced by the total of capital gains exemptions claimed in earlier years. This is the only circumstance in which a capital loss reaches ordinary income.
It matters because a final return often carries an unusually large income from the deemed disposition of registered accounts, and an old carryforward can offset part of it — the mechanics are in the final return.
The carryforward balance appears on the notice of assessment each year, which is the only place it is recorded. An executor working through a final return should look for it there before assuming there is nothing to apply, because a loss realised in a market decline two decades earlier is easy for a family to have forgotten entirely.
The imported three-thousand-dollar figure does real damage. People sell at a loss expecting it to shelter salary, discover it shelters nothing that year, and conclude the loss was wasted. It was not wasted — it just needs a gain, and often one already sitting in a return filed two years ago.
FAQ
Can capital losses reduce my regular income?
No, except on a final return at death. In every other year a net capital loss offsets capital gains only, and Canada has no annual allowance against ordinary income.
How long can I carry a capital loss forward?
Indefinitely. There is no expiry on a net capital loss carryforward, though it can only ever be applied against capital gains.
Should I carry back or carry forward?
Check the three prior years first. A carryback recovers tax already paid and produces a refund, while a carryforward waits for a future gain that may not arrive.
Sources
Regulator references
- Capital gains (line 12700) · Canada Revenue Agency · 2025How capital gains and losses are calculated, reported and carried.Last verified: 2026-09-07
- Canadian income tax rates for individuals · Canada Revenue Agency · 2025The federal and provincial rate brackets a withdrawal is taxed against.Last verified: 2026-09-07
Calculator unit tests · the assertions this page's worked example is checked against, and their last result
Changelog
- 2026-09-07 — initial publish (new format)
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Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.