The tax treatment for income generated from Comprehensive Investment Accounts (IMAs) in South Korea is a developing area. Currently, the prevailing understanding and planned legislative action indicate that IMA income will be classified as dividend income.
This means that the income derived from IMAs will be subject to a withholding tax rate of 15.4%, similar to interest income from bank deposits.
However, a crucial point to consider is the financial income aggregation rule. If your total annual financial income (including interest, dividends, and IMA income) exceeds 20 million KRW, you will be subject to comprehensive income tax. This can result in a significantly higher tax rate, potentially up to 49.5%, depending on your overall income bracket.
Given that IMAs are typically structured as lump-sum payments at maturity, longer investment periods could lead to a substantial accumulation of income, increasing the likelihood of exceeding the 20 million KRW threshold and triggering comprehensive income tax.
It's important to note that the regulatory landscape for IMAs is still evolving. While the classification as dividend income is the current direction, further legislative changes or clarifications may occur.