Most investors think a losing position is a failure. In a taxable brokerage account, a losing position is a gift. Tax loss harvesting is the practice of selling investments at a loss on purpose, using those losses to offset gains and ordinary income, and then replacing the position so your portfolio stays roughly the same. Done correctly, it adds 0.5 to 1.0 percent in after-tax return per year. Done across decades, that is real money.
The basic mechanics are simple. The IRS lets you net capital losses against capital gains in the same year with no limit. If you have $20,000 in long-term capital gains and $20,000 in capital losses, you owe zero tax on the gains. After offsetting all gains, you can also use up to $3,000 of remaining losses against ordinary income each year. Anything beyond that carries forward indefinitely until you use it. A $40,000 loss in 2026 can shield gains and income for the next decade if you do not have offsetting gains right away.
Tennessee residents have a particular advantage. Tennessee has no state income tax on capital gains or wage income, so the harvesting savings are entirely federal. A high earner in the 23.8 percent long-term capital gains bracket who harvests $20,000 in losses against $20,000 in gains saves $4,760 in federal tax. A short-term capital gain in the 35 percent bracket plus 3.8 percent net investment income tax saves $7,760 on the same offset. The bigger your gain, the more the harvest is worth.
The wash sale rule is the trap. If you sell a position at a loss and buy the same security or a substantially identical one within 30 days before or after the sale, the loss is disallowed. The 30 day window applies on both sides, which means a 61 day blackout total. The rule covers stocks and options. The IRS has been silent on whether it applies to crypto, but Congress has been close to closing that loophole every year, so most CPAs treat crypto as if the rule applies.
The clean way to harvest a loss without breaking the wash sale rule is to swap into a similar but not identical security. If you sell VTI at a loss, you can buy ITOT or SCHB the same day. They track different indexes but have nearly identical exposure to the US total market. If you sell SPY, swap into VOO or IVV. After 31 days, you can swap back if you prefer the original. Most investors just stay in the replacement.
The harvesting calendar matters. The best time to harvest is during a market drawdown, when more positions are underwater. December is the traditional harvesting month, but waiting until December means missing opportunities earlier in the year. A better practice is to scan the portfolio every quarter, harvest available losses, and reset. The 2022 bear market created harvesting opportunities that compound for years. Investors who harvested in October 2022 are still using those losses against gains in 2026.
Direct indexing has changed the game for taxable accounts above $250,000. Instead of holding a single index fund, the investor owns the underlying 500 to 1,500 stocks directly. The platform automatically harvests losses on individual positions whenever they go underwater, even when the index as a whole is up. Wealthfront, Frec, and Schwab Personalized Indexing all run this for 0.20 to 0.40 percent annually. Studies from the 2024 Journal of Portfolio Management show direct indexing harvests 1.0 to 2.5 percent in additional after-tax return per year compared to a single index fund, depending on volatility.
The bigger your account, the more direct indexing matters. Below $100,000, the simpler approach of harvesting one or two positions a quarter inside a regular brokerage works fine. Above $250,000, the math on direct indexing usually pencils out. Above $1 million, it almost always does. The platforms calculate the breakeven for you.
There are limits worth knowing. Harvested losses lower your cost basis in the replacement position, which means you will eventually pay tax on the deferred gain when you sell. The benefit is the time value of money. A dollar of tax saved today is worth more than a dollar paid in 20 years, especially if you hold to death and use the stepped-up basis to wipe out the deferred gain entirely. Most long-term investors plan to do exactly that.
The other limit is behavioral. Some investors get too clever and turn harvesting into a reason to overtrade. The point is to harvest opportunistically, not to constantly reshape the portfolio. A simple rule helps. Harvest only when a position is down 10 percent or more from cost basis, and only when the harvested loss is at least $1,000. Below those thresholds, the savings do not justify the paperwork.
The reporting is straightforward. Your broker sends a 1099-B at year end showing all sales with cost basis and gain or loss. Your CPA matches it to Schedule D and Form 8949. Direct indexing platforms send the same forms, just with more lines. Done correctly, the IRS rarely questions a properly reported harvest. Done sloppily with wash sale violations, the IRS adjusts your basis and disallows the loss. The discipline of staying out of the same security for 31 days is the entire game.
Most investors leave thousands on the table every year by not harvesting. The tool is sitting in their account. They just have not used it.
