What it means
When you sell an investment for less than you paid, you realise a capital loss. Tax rules in many countries let you subtract those losses from your capital gains, which reduces the tax bill.
Harvesting means doing this deliberately instead of waiting for the investment to recover. Doing it by hand requires constant monitoring, so digital platforms, often called robo-advisors, automate the process.
Their software scans a portfolio daily, finds positions with losses, sells them and buys a similar but not identical replacement. The investor stays invested in the market and only the tax position changes.
The replacement matters because of wash-sale rules. In the United States, for example, a loss is generally disallowed if you buy a substantially identical security within a window of about 30 days before or after the sale.
The software therefore swaps one fund for a close cousin, such as a different index fund tracking a similar market, and tracks the dates carefully. It is important to understand that harvesting usually defers tax and does not erase it.
The replacement is bought at a lower price, so its cost basis (the amount used to calculate future gains) is lower, and a bigger gain is taxed when it is finally sold. The benefit comes from paying tax later, from using losses against higher-taxed gains, and from the chance to hold the investment until a more favourable time.
Not everyone benefits equally. Investors with large taxable gains and taxable accounts gain most, while those who invest only through tax-sheltered retirement accounts gain nothing, since there are no taxes to reduce.
Fees, tax rules and personal circumstances all matter, and tax advice is worthwhile before relying on the service.
In practice
Real-world examples.
Example
A software engineer with a taxable investment account sees a technology fund fall by 12% in a market dip. The platform sells it, buys a similar fund and records a loss that cancels part of the gain on her company shares.
Example
A couple sells a rental property at a profit and expects a large capital gains bill. Their robo-advisor harvests losses across their portfolio during the year, lowering the net taxable gain.
Example
A retiree with only tax-sheltered accounts signs up for the service, then learns that it provides no benefit for his accounts. He switches to a plain low-cost portfolio and saves the extra fee.
Formula
Calculation
Tax Saving = Harvested Loss x Tax Rate on the Gains It Offsets
Worked example: An investor holds a fund bought for $30,000 that is now worth $22,000. She also sold another investment earlier in the year for an $8,000 gain. The tax rate on her gains is 20%.
Loss harvested = $30,000 - $22,000 = $8,000
Gain offset = $8,000, so her taxable gain falls from $8,000 to $0
Tax saving = $8,000 x 20% = $1,600
Without harvesting, she would have paid $8,000 x 20% = $1,600 in tax. The replacement fund is bought at $22,000, so a later sale at $30,000 would create an $8,000 gain, which means the $1,600 is largely a deferral. If she holds it for years, the value of the delay can still be worthwhile.Case study
Seen in the real world.
Windward Wealth is a fictional digital adviser that offers automated tax loss harvesting. In this illustrative case, it onboarded a client named Priya who had $200,000 in a taxable account and expected $15,000 of gains from selling a business share.
During a rough quarter, the software harvested $12,000 of losses by switching three funds into near-equivalents. These offset most of the gain, and at a 20% tax rate Priya's bill fell by $2,400.
The platform also warned her that her cost basis was now lower and that the saving was mostly a deferral. Priya kept a record of each trade for her accountant, and she understood that the service helped most in years when she had gains to offset.
Watch out
Common mistakes.
- Believing harvesting avoids tax for ever. It usually lowers the cost basis, so tax is due later unless you hold the asset for the long term or the rules change.
- Buying the same fund straight back. Doing so within the wash-sale window can cancel the loss for tax purposes.
- Using the service in tax-sheltered accounts. Without taxable gains, there is nothing to offset.
Questions
People also ask.
Is robo tax loss harvesting worth the fee?
It depends on how much taxable income and gains you have, the tax rates and the cost of the service. For small or sheltered accounts, the benefit may be tiny.
Can losses be used against ordinary income?
In many tax systems, a limited amount of net capital loss can be set against other income each year, with the rest carried forward. The limit is set by the tax authority, so check the current rule.
What happens to unused losses?
Most systems let you carry them forward to future years, so they can offset later gains.
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