What Are Short-Term Capital Gains?
Short-term capital gains are profits from selling assets held for one year or less. Unlike long-term gains, short-term gains do not receive preferential tax treatment. They are added to your ordinary income and taxed at your marginal income tax rate, which can be as high as 37% for federal taxes.
This higher tax rate makes a strong case for holding investments longer than one year when possible. The difference between short-term (up to 37%) and long-term (0-20%) rates can save thousands of dollars on the same gain.
A $15,000 gain taxed at 24% (short-term) costs $3,600 in federal taxes. The same gain held for over one year and taxed at 15% (long-term) costs only $2,250. That is $1,350 in savings just for holding 12+ months.
2026 Federal Income Tax Brackets (Short-Term Rates)
| Taxable Income | Tax Rate | Tax on $15K Gain | Notes |
|---|---|---|---|
| $0 - $11,600 | 10% | $1,500 | Lowest bracket |
| $11,601 - $47,150 | 12% | $1,800 | Most common for low income |
| $47,151 - $100,525 | 22% | $3,300 | Middle income |
| $100,526 - $191,950 | 24% | $3,600 | Upper middle income |
| $191,951 - $243,725 | 32% | $4,800 | High income |
| $243,726 - $609,350 | 35% | $5,250 | Very high income |
| Over $609,350 | 37% | $5,550 | Top bracket |
- 1Total taxable income = $75,000 + $15,000 = $90,000
- 2Federal bracket at $90,000 (single) = 22%
- 3Federal tax = $15,000 × 22% = $3,300
- 4State tax = $15,000 × 5% = $750
- 5NIIT: income below $200K threshold, so $0
- 6Total tax = $3,300 + $750 = $4,050
- 7After-tax gain = $15,000 - $4,050 = $10,950
Minimizing Short-Term Capital Gains Tax
- Day traders face the highest tax burden because all gains are short-term
- The 3.8% NIIT applies to investment income when MAGI exceeds $200K (single) or $250K (married)
- Qualified small business stock (QSBS) may exclude up to $10 million in gains if held 5+ years
- Installment sales can spread gain recognition across multiple tax years
- Consider the impact of short-term gains on your adjusted gross income, which affects other deductions and credits
Short-Term Capital Gains vs. Ordinary Income
Short-term capital gains — profits on assets held 12 months or less — are taxed at the same rates as your ordinary income, not the preferential long-term rates. This means your short-term gains are stacked on top of your other income (wages, dividends, business income) to determine your overall tax bracket. For high earners, short-term capital gains can be taxed at 32%, 35%, or even 37% at the federal level, plus state income taxes. This is why the choice of holding period is one of the most impactful tax decisions an investor can make.
Active traders and day traders are particularly affected by short-term capital gains treatment, since virtually all of their profits are short-term. Some professional traders elect 'mark-to-market' accounting under Section 475(f), which allows them to deduct trading losses more broadly but also means all gains are treated as ordinary income regardless of holding period. Wash-sale rules also apply to short-term traders: if you sell a stock at a loss and repurchase it within 30 days before or after the sale, the loss is disallowed and added to the cost basis of the repurchased shares.
Tax-Loss Harvesting to Offset Short-Term Gains
Tax-loss harvesting is the practice of selling losing positions to generate capital losses that offset capital gains. Short-term losses first offset short-term gains (which are taxed at higher rates), making this strategy particularly valuable for active traders. Capital losses can offset capital gains dollar-for-dollar, and up to $3,000 of excess losses can be deducted against ordinary income annually. Unused losses carry forward indefinitely. Automated tax-loss harvesting is a core feature of robo-advisors like Betterment and Wealthfront, and studies show it can add 0.5-1.5% in after-tax returns annually for taxable investors.
When tax-loss harvesting, be careful not to trigger wash-sale rules by repurchasing the same or 'substantially identical' security within 30 days before or after the sale. If you sell SPY at a loss, you cannot buy SPY back for 30 days (but you can buy VOO or a different S&P 500 ETF immediately, as the IRS has not ruled these substantially identical). Plan your tax-loss harvesting around this 30-day window to capture the loss while maintaining market exposure.
