Tax-Loss Harvesting
Selling investments at a loss to offset capital gains and reduce taxable income, while typically reinvesting in similar (but not "substantially identical") assets to preserve market exposure.
How tax-loss harvesting works
The basic mechanism:
- Sell losing position to realize a capital loss.
- Loss offsets capital gains elsewhere — reducing taxes owed.
- Excess losses offset up to $3,000 of ordinary income per year (US).
- Carry forward unused losses to future years indefinitely.
- Reinvest proceeds in similar (but not identical) holding to maintain market exposure.
The process converts paper losses into actual tax savings while staying invested.
The wash-sale rule
Critical constraint:
- Cannot buy "substantially identical" security within 30 days before or after sale.
- Violation disallows the loss for tax purposes.
- Applies across accounts — including spouse's, IRAs.
- Crypto exemption (currently in US) — wash-sale rule doesn't formally apply, though regulation may change.
Workarounds use similar but not identical replacement securities.
Practical examples
Common applications:
- Sell S&P 500 ETF (e.g., VOO) at loss → buy similar but not identical ETF (e.g., IVV).
- Sell individual stock at loss → buy sector ETF temporarily.
- Crypto — sell BTC at loss, immediately rebuy (rule doesn't apply currently).
After 31 days, can return to original holding if desired.
Why tax-loss harvesting matters
Several practical benefits:
- Direct tax savings — captured loss reduces current-year taxes.
- Tax-rate arbitrage — short-term losses offset short-term gains (taxed higher).
- Carry-forward value — losses don't expire.
- Deferral effect — pay less now, more later (if ever).
Studies suggest disciplined harvesting can add 0.5-1% annually to after-tax returns for some portfolios.
Limitations
Several caveats:
- Most valuable in taxable accounts; doesn't apply in IRAs, 401(k)s.
- Cost basis tracking is essential.
- Doesn't help if you have only gains and no losses.
- Behavioral risk — over-trading in name of harvesting.
The benefit is real but bounded.
What individuals should know
For investors:
- Worth doing in taxable accounts with losses.
- End-of-year review — common time to harvest.
- Beware wash sales — track replacement securities.
- Don't let tax tail wag investment dog — don't sell appreciated assets just to avoid taxes.
Tax-loss harvesting is one of the more-reliable ways to add after-tax return. The gains are modest but compound over time, particularly for higher-income investors with significant taxable-account holdings.