Losing trades have one consolation prize: they can lower your tax bill. Tax-loss harvesting is the deliberate version — selling losers to offset gains, banking the deduction, and staying invested the whole time.
Answer first: tax-loss harvesting means selling an investment that is sitting at a loss so the loss becomes “realized” and can be used on your tax return — first to cancel out capital gains you realized elsewhere, then (in the U.S.) to deduct up to $3,000 per year against ordinary income ($1,500 if married filing separately), with anything left over carried forward to future years indefinitely. The position is typically replaced with a similar-but-not-identical investment, so your market exposure barely changes while the tax loss is locked in.
Suppose in one year you sold a winner for a $10,000 gain and you are holding another position down $14,000. Harvesting that loss cancels the entire $10,000 gain — no capital gains tax on it — then knocks $3,000 off your ordinary taxable income, and carries the remaining $1,000 forward to next year. The loss was already real on your screen; harvesting just makes the tax code acknowledge it.
U.S. rules net losses in a set sequence:
Because short-term gains are taxed as ordinary income, losses that offset them are the most valuable kind — a detail that shapes when experienced investors choose to harvest. See what are capital gains taxes for the gain side of the ledger.
You cannot sell a stock, claim the loss, and buy it right back. The wash sale rule disallows the loss if you purchase the same or a “substantially identical” security within 30 days before or after the sale — a 61-day danger window. Harvesters route around it by swapping into a similar-but-different holding (for example, one broad index fund for another that tracks a different index) or by waiting out the window. Get this wrong and the harvested loss is deferred into the replacement shares’ cost basis instead of landing on this year’s return.
Rule of thumb: harvest the loss, keep the exposure, respect the 61-day window. All three at once — that is the whole craft.
Less than the brochures imply, more than zero. Offsetting a short-term gain saves tax at your marginal income rate; the $3,000 ordinary-income deduction is worth $660–$1,110 a year to someone in the 22–37% brackets. But remember that harvesting usually lowers your cost basis — you may owe more capital gains tax later when you finally sell the replacement. Much of the benefit is deferral (a tax-free loan from the future), which is genuinely valuable, plus a smaller permanent gain if you later sell at lower long-term rates or pass assets on. It is compounding’s quieter cousin, not a magic trick.
Not tax advice: thresholds and rules here describe long-standing U.S. federal treatment in plain language and can change; states differ too. Confirm current figures at irs.gov or with a tax professional before acting. Educational content only.
Related reading: the wash sale rule, the capital gains tax calculator to estimate what a harvest could offset, and capital gains taxes explained.
Last updated July 2, 2026 · Written by Mustafa Bilgic. Educational only — not financial advice.
Selling an investment at a loss on purpose so the loss can offset your capital gains — and up to $3,000 of ordinary income per year in the U.S. — while you move the money into a similar investment to stay in the market.
After offsetting capital gains, up to $3,000 per year of net capital loss ($1,500 married filing separately) can be deducted against ordinary income. The excess carries forward to future years.
Under U.S. federal rules, unused capital losses carry forward indefinitely for individuals, offsetting future gains and up to $3,000 of income each year until used up.
Not within 30 days before or after the sale — that triggers the wash sale rule and disallows the loss for now. Swap into a similar but not substantially identical investment or wait out the window.
No. Those accounts have no taxable capital gains to offset, and losses inside them are not deductible.