By James Walker — CFP® candidate, Boston MA · Updated January 2026
Tax loss harvesting is one of those CFP topics that sounds technical but is actually conceptually simple: you intentionally sell losing investments to generate a tax deduction, then reinvest the proceeds into something similar to maintain your market exposure. Done right, it can add real money to your after-tax returns without changing your underlying investment strategy.
What is tax loss harvesting?
Tax loss harvesting (TLH) is the practice of selling securities at a capital loss to offset capital gains tax liability and reduce taxable income. Per IRS Topic 409, capital losses first offset capital gains of the same type (short-term losses offset short-term gains, etc.), then offset opposite-type gains, then offset up to $3,000 of ordinary income per year, and finally carry forward indefinitely to future tax years.
How does the math work?
Say you bought 100 shares of Vanguard’s VTI at $250/share ($25,000) and it dropped to $220/share ($22,000). You sell, realizing a $3,000 capital loss. You immediately reinvest the $22,000 into Schwab’s SCHB (a similar but not identical total US stock market ETF). Your portfolio exposure is essentially unchanged, but you now have a $3,000 capital loss to offset taxes.
For a 22%-bracket worker with no capital gains, that $3,000 loss reduces federal tax owed by $660. State tax savings add more depending on your state (CA at 9.3% = $279 extra; MA at 5% = $150 extra). Total savings: $810-940 in one tax year.
What is the wash sale rule?
This is the trap that disqualifies many DIY TLH attempts. Per IRS Publication 550, a wash sale occurs when you buy a substantially identical security within 30 days before OR after the loss sale. If triggered, the loss is disallowed and the disallowed loss is added to the basis of the new purchase.
Key wash sale considerations:
- The 30-day window applies in BOTH directions (61 days total)
- Wash sales apply across all your accounts including IRAs (per IRS Rev. Rul. 2008-5)
- Wash sales apply to your spouse’s accounts (joint taxation)
- “Substantially identical” is not formally defined – VTI and VOO are different (different indexes), VTI and ITOT are debatable, two share classes of the same fund are clearly identical
- Reinvested dividends in DRIP can accidentally trigger wash sales – turn off DRIP in the same security during your TLH window
Which accounts can I tax-loss harvest in?
Only taxable brokerage accounts. Traditional IRA, Roth IRA, 401(k), and HSA gains/losses are not reportable on Schedule D – they grow tax-deferred or tax-free already, so there is no tax to harvest. TLH is purely a taxable-account strategy.
What is the $3,000 ordinary income offset?
After offsetting all capital gains (short and long), up to $3,000 of remaining net capital loss can offset ordinary income each year. Excess losses carry forward indefinitely with no expiration. A retiree sitting on $20,000 in carried-forward losses can use $3,000 per year for the next ~7 years to reduce taxable income from Social Security, pensions, or required minimum distributions.
When does tax loss harvesting matter most?
TLH is most valuable when:
- You are in the 24%+ federal bracket (each dollar of loss saves 24+ cents)
- You live in a high-tax state (CA, NY, NJ, MA, OR add 5-13% on top)
- You have realized capital gains to offset (rebalancing, fund changes)
- You have a sizable taxable account ($50K+ makes it worth the effort)
- Market volatility creates harvesting opportunities (bear markets are TLH gold)
It is essentially worthless for an investor in the 10-12% bracket with only retirement accounts.
How do robo-advisors automate TLH?
Wealthfront and Betterment scan client portfolios daily and automatically execute TLH when individual lots drop below cost basis. They swap into a similar-but-not-identical ETF (VTI sold, SCHB purchased) to avoid wash sale. Wealthfront’s Direct Indexing service at $100K+ extends this to individual stocks within the S&P 500, capturing significantly more loss opportunities than ETF-level harvesting alone.
Schwab Intelligent Portfolios offers TLH only on accounts above $50,000. Vanguard Digital Advisor does not offer TLH. For DIY investors, you can do this manually at Fidelity, Vanguard, or Schwab by setting price alerts and tracking lots in your tax software.
What are the practical TLH pitfalls?
- Wash sale violations – the most common DIY mistake; always check ALL accounts including IRAs and spouse’s accounts
- Harvesting in the wrong year – if you have low income this year (say a sabbatical), saving losses for a future high-income year is more valuable
- State tax mismatches – some states do not conform to federal capital loss treatment
- Decreasing cost basis – over many years of TLH, your cost basis drops, meaning higher future gains taxes (TLH is a deferral, not always an elimination)
- Trading costs – at most modern brokers commissions are zero, but bid-ask spreads can still cost on illiquid ETFs
Related Reading on FinanceFernly
- Best robo-advisors compared
- Index fund basics
- How to read your pay stub
- Filing taxes in multiple states
Frequently Asked Questions
Can I harvest losses in my Roth IRA or 401(k)?
No. Losses in tax-advantaged accounts are not reportable on Schedule D because there is no tax liability on gains in those accounts either. Tax loss harvesting only applies to taxable brokerage accounts. This is one reason high earners with large taxable accounts benefit much more from TLH than younger investors with only retirement accounts.
Can I just sell and rebuy the same fund the next day?
No. That triggers a wash sale and the loss is disallowed. The wash sale rule applies for 30 days before AND 30 days after the loss sale (61-day total window). Buy a substantially similar but not identical ETF instead – like swapping VTI for SCHB, or VOO for IVV.
Does tax loss harvesting reduce my long-term returns?
On a pre-tax basis, slightly – because you are essentially locking in a slightly different basis. On an after-tax basis, TLH typically adds 0.4-1% per year of after-tax return for investors in the 24%+ bracket. The Vanguard research papers on TLH put the benefit at roughly 50-100 basis points for taxable accounts.
How often should I tax-loss harvest?
Robo-advisors do it daily. DIY investors typically batch around year-end (October-December) and during market drops. There is no benefit to harvesting losses every day if you do not have offsetting gains – the limit is $3,000 of ordinary income offset per year plus any gains.
What happens to harvested losses if I die?
Carried-forward losses do not pass to your heirs – they expire with you. This is why some retirees aggressively use their losses against ordinary income while alive rather than letting them accumulate indefinitely. Your heirs get a stepped-up basis on inherited assets, eliminating the embedded gains anyway.
Final thoughts from a CFP candidate
Tax loss harvesting is a real tool with real numbers, but it is also frequently oversold. For someone in the 12% bracket with mostly retirement accounts, TLH adds essentially nothing. For someone in the 32%+ bracket with a $500K+ taxable account in a high-tax state, TLH can add multiple thousands per year in after-tax returns.
If you want automated TLH and have a $50K+ taxable account, Wealthfront or Betterment earn their fee through this feature alone for many clients. If you DIY, be religious about avoiding wash sales and document everything – the IRS audits Schedule D more aggressively than most parts of the return.
