What is Capital Loss? (Plain English Definition)
Definition: A capital loss occurs when you sell an investment for less than you originally paid for it.
Capital Loss Explained Simply
A capital loss is the opposite of a capital gain -- it happens when you sell an investment for less than your purchase price. If you bought ETF shares at $100 and sold them at $80, you have a capital loss of $20 per share. Like capital gains, losses are only realized when you actually sell.
Capital losses have a silver lining: they can be used to offset capital gains for tax purposes. If you realized $5,000 in capital gains and $3,000 in capital losses during the same year, you only pay taxes on the net $2,000 gain. If your losses exceed your gains, you can deduct up to $3,000 of net losses against your ordinary income per year, and carry any remaining losses forward to future tax years.
This tax treatment creates opportunities for a strategy called tax-loss harvesting, where investors intentionally sell losing positions to capture the tax benefit and then reinvest in a similar (but not identical) investment to maintain their market exposure.
Capital Loss Example
You own two ETFs. ETF A has gained $4,000 and ETF B has lost $2,500. If you sell both, you have a net capital gain of $1,500 ($4,000 minus $2,500). At a 15% long-term rate, you owe $225 in taxes instead of $600 on the full $4,000 gain. The $2,500 loss saved you $375 in taxes. If ETF B had lost $6,000 instead, you could offset all $4,000 in gains plus deduct $2,000 against ordinary income, carrying the remaining $0 forward.
Why Capital Loss Matters for ETF Investors
Capital losses are an important tax planning tool for ETF investors. Nobody likes losing money on an investment, but strategically realizing losses can reduce your overall tax bill. This is especially valuable in taxable brokerage accounts where capital gains taxes can take a meaningful bite out of your returns. For ETF investors, the ability to harvest losses while maintaining similar market exposure is a unique advantage. You can sell a losing S&P 500 ETF and immediately buy a different S&P 500 ETF or total market ETF, capturing the tax loss while staying invested in the market. Just be aware of the wash-sale rule, which disallows the loss if you buy a substantially identical investment within 30 days.
Capital Loss vs Capital Gain
| Capital Loss | Capital Gain |
|---|---|
| A capital loss occurs when you sell an investment for less than you originally paid for it. | See full definition of Capital Gain |
While capital loss and capital gain are related concepts, they serve different purposes in the world of ETF investing. Understanding both terms helps you make more informed decisions about which funds to include in your portfolio and how to evaluate their performance.
Related Terms
Deepen your understanding of ETF investing by exploring these related concepts:
Capital Gain
A capital gain is the profit earned when you sell an investment for more than you originally paid for it.
Tax-Loss Harvesting
Tax-loss harvesting is the strategy of selling investments at a loss to offset capital gains taxes, then reinvesting in similar assets to maintain market exposure.
Tax Efficiency
Tax efficiency measures how well an investment minimizes the taxes investors owe, with ETFs being among the most tax-efficient investment vehicles.
Unrealized Gain (Paper Gain)
An unrealized gain is an increase in the value of an investment you still hold, which becomes a realized gain only when you sell.
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