The Difference Between Dividend Tax and Capital Gains Tax

Income earned from stocks splits broadly into two branches. One is "dividend income," where the company shares out its profit; the other is "transfer income," which arises when you buy cheap and sell dear.

Both are "income," but our tax law puts these two in entirely different boxes to calculate. Dividend income is bundled with interest income as "financial income," while transfer income is set apart on its own and treated as "classified taxation."

So the rate, the filing method, and the way losses are recognized are all different. If you don't know this difference, you'll be flustered thinking, "I clearly made money, so why was this much taken?"

When you receive a dividend, the brokerage deducts 15.4% on its own and deposits the rest into your account. This 15.4% is income tax 14% plus local income tax 1.4% (10% of the income tax).

For most people it ends here. If your "financial income" combining interest and dividends is 20 million won or less a year, the tax is concluded with this 15.4% withholding (separate taxation).

But if your financial income exceeds 20 million won, the story changes. The excess is combined with other income like earned income and taxed comprehensively, and the more income you have, the higher the rate goes, up to 49.5% (including local tax). It's a structure where the more dividends you receive, the heavier the tax burden.

Capital gains tax is paid only "when you sell and realize a gain" on a stock. No matter how much the valuation rises, if you don't sell there is no tax.

For domestic listed stocks, trading gains are generally tax-exempt for ordinary individuals (small shareholders). By contrast, for overseas stocks like the U.S. or China, if your net annual gain exceeds 2.5 million won, 22% (national tax 20% + local tax 2%) attaches to the excess.

The biggest difference is "who handles the tax." Dividend tax is deducted automatically by the brokerage, but overseas stock capital gains tax you must file and pay yourself on Hometax the following May. If you forget, penalty taxes are added.

The most important practical difference is "loss treatment."

Transfer income can offset gains and losses against each other within the same year. If you made 5 million won on stock A and lost 3 million won on stock B, the tax is levied on the net gain of 2 million won. This is called "gain-loss netting."

By contrast, dividend income has no concept of "loss" at all. That's because a dividend is confirmed as income the moment you receive it. Even if, after receiving 1 million won in dividends, that stock crashes and you lose 2 million won, that stock loss does not reduce the dividend tax.

So the strategy for saving tax is also completely different for the two types of income. For transfer income, "when and how much you realize" drives the tax; for dividend income, "whether you cross the 20 million won financial income line" is the key.