By Christian BrinkleyLicensed NC Insurance Agent, NPN 22217190, NC Life & Health · Updated October 14, 2026 · 4 min read
Every investor ends up holding something that went down. It feels bad. Tax loss harvesting is the one move that turns a losing investment into something useful: a tax break. The idea is simple. If you sell an investment for less than you paid, you have a capital loss. That loss can offset capital gains you made elsewhere. Sold one stock at a profit and another at a loss? The loss cancels out some or all of the gain, and you only pay tax on the net amount. If your losses are bigger than your gains, you can generally use the extra to offset a limited amount of ordinary income each year, and carry the rest forward to future years. The exact annual limit changes, so check the current rule.
Notice what is happening here
You are not changing your overall investment outcome. The loss was already real. You are just choosing when to recognize it for tax purposes, and putting it to work against gains you would otherwise pay tax on.
Here is a plain example. Say you bought two stocks a while back. One is up, one is down. If you sell the winner, you owe tax on the gain. But if you also sell the loser in the same year, the loss offsets the gain. Your portfolio ends up in roughly the same place, minus the loser you did not want anyway, and your tax bill is smaller.
Who does this actually help? Mostly people with taxable investment accounts, meaning regular brokerage accounts, not retirement accounts. Inside an IRA or 401(k), gains and losses do not get taxed year to year, so harvesting does nothing for you there. It is a taxable-account strategy.
It helps most when you actually have gains to offset
If you sold investments at a profit this year, or your mutual funds spit out capital gains distributions, harvested losses can soak those up. It also helps high earners more, because they face higher tax rates on gains, so each dollar of offset is worth more. And it helps people who rebalance anyway. If you were going to sell the loser to clean up your portfolio, doing it before year end turns a chore into a tax benefit.
Now the big catch: the wash sale rule. The IRS does not let you sell something at a loss, claim the tax break, and immediately buy it right back. If you buy the same or a “substantially identical” investment within 30 days before or after the sale, the loss is disallowed. The 61-day window, 30 days on each side plus the sale day, is the danger zone.
There is a common workaround
You sell the losing investment and buy something similar but not substantially identical. Sell one large-company index fund and buy a different large-company index fund from another provider, for example. You stay invested in the same part of the market, but it is a different security, so the wash sale rule should not apply. “Substantially identical” is fuzzy around the edges, so this is one of those areas where a tax professional earns their keep.
And keep records
Your broker will send tax forms, but wash sale tracking across multiple accounts is on you. If you harvest regularly, a simple spreadsheet with sale dates, amounts, and replacement purchases will save you a headache in April.
The bottom line: tax loss harvesting is a legitimate, mainstream strategy for taxable accounts. Sell losers you do not want, use the losses against gains, respect the 30-day wash sale window, and do not sell winners-wearing-loser-costumes just for the tax break.
This is general information, not tax advice. The annual limits and rules change, so check the current year's details at irs.gov, and talk to a tax professional before you start selling.
Questions people ask me about this
What should I know about tax loss harvesting?
You are not changing your overall investment outcome. The loss was already real. You are just choosing when to recognize it for tax purposes, and putting it to work against gains you would otherwise pay tax on. Here is a plain example. Say you bought two stocks a while back. One is up, one is down.
What does “notice what is happening here” mean?
You are not changing your overall investment outcome. The loss was already real. You are just choosing when to recognize it for tax purposes, and putting it to work against gains you would otherwise pay tax on. Here is a plain example. Say you bought two stocks a while back. One is up, one is down.
What does “it helps most when you actually have gains to offset” mean?
If you sold investments at a profit this year, or your mutual funds spit out capital gains distributions, harvested losses can soak those up. It also helps high earners more, because they face higher tax rates on gains, so each dollar of offset is worth more. And it helps people who rebalance anyway.
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