Tax Loss Harvesting
An investment strategy of selling assets at a loss to offset capital gains or ordinary income, reducing current tax liability while maintaining portfolio exposure.
Tax loss harvesting is the strategic practice of selling investment positions that have declined in value to realize a capital loss, which can then be used to offset capital gains realized elsewhere in the portfolio — reducing current tax liability. If capital losses exceed capital gains in a year, up to $3,000 of net losses can offset ordinary income, with any remaining losses carried forward to future years.
The mechanics are straightforward: if an investor holds Stock A with $10,000 in unrealized gains and Stock B with $8,000 in unrealized losses, selling both realizes $2,000 in net capital gains. Selling only Stock B without selling Stock A realizes $8,000 in capital losses that offset future gains. The portfolio can maintain similar market exposure by immediately purchasing a similar (but not substantially identical) security, preserving the investment thesis while banking the tax benefit.
The 'wash sale rule' (IRC Section 1091) is the critical constraint: if you sell a security at a loss and buy the same or a 'substantially identical' security within 30 days before or after the sale, the loss is disallowed and added to the cost basis of the repurchased shares. Proper tax loss harvesting requires substituting similar but not identical securities during the wash sale window.
Automated tax loss harvesting is a flagship feature of robo-advisors like Betterment, Wealthfront, and Schwab Intelligent Portfolios, which monitor portfolios daily for loss harvesting opportunities and execute trades automatically while managing wash sale risk. Research suggests daily automated harvesting can add 0.5–1.5% in annual after-tax returns.
For high-net-worth investors and family offices, tax loss harvesting is coordinated with overall tax planning — timing of gains, portfolio rebalancing, charitable giving — through a multi-asset, cross-account framework.
FAQs
What is the wash sale rule and how does it affect tax loss harvesting?
The wash sale rule disallows a capital loss if you buy the same or substantially identical security within 30 days before or after the sale. To harvest the loss, you must wait 31 days before repurchasing, or immediately buy a similar but not identical investment (e.g., sell an S&P 500 ETF and buy a different broad market ETF) to maintain market exposure.
Is tax loss harvesting only valuable for high earners?
Tax loss harvesting is most valuable for investors in higher tax brackets (23.8% long-term capital gains rate for high earners vs. 0–15% for others) and for those with significant taxable investment accounts. Investors in low tax brackets or primarily in tax-advantaged accounts (IRA, 401k) see limited benefit because gains are already tax-deferred or tax-free.
What happens to harvested losses that aren't used in the current year?
Capital losses that exceed capital gains in a year are first applied against up to $3,000 of ordinary income. Any remaining net capital loss is carried forward indefinitely (not limited to a specific period) to offset future capital gains and income. The character (short-term vs. long-term) of the loss is preserved in carryforward.
Related Terms
R&D Tax Credit
A federal and state tax incentive allowing businesses to claim a credit for qualifying research and development expenditures.
Bonus Depreciation
A tax incentive allowing businesses to immediately deduct a large percentage of the cost of eligible property in the year it is placed in service.
Estimated Tax
Quarterly tax payments required from self-employed individuals and businesses that expect to owe $1,000 or more in taxes not covered by withholding.
