If you make a short-term capital gain, it's added to your income and taxed at your regular income tax rate. For example, let's say you purchase $10,000 of a particular stock in February, then sell it for $15,000 in November of the same year. You'll have a capital gain of $5,000. Since the gain is considered short-term, it will be taxed at your regular income tax rate. Long-term capital gains are taxed at a lower rate than short-term gains. In a hot stock market, the difference can be significant to your after-tax profits. Short-term gains are taxed just like income. If you hold your stock for one year or less, then it will be taxed as short-term capital gains. This is pretty straightforward to determine: Short-term capital gains tax rates are equal to your marginal tax rate, or tax bracket.