Korean Other Income Tax Calculator

Fees for giving a lecture, writing an article, winning a competition or handing over a shop's goodwill are neither salary nor business income. Korean tax law groups such payments as "other income" and taxes them on their own terms. Enter the amount received and the kind of income, and this calculator shows the tax the payer withholds, the amount that actually reaches you, and that tax as a percentage of the payment.

The key point is that the tax attaches not to the whole payment but to "other income amount", the payment less deemed necessary expenses. Preparing and travelling for a lecture costs money, but keeping every receipt is impractical, so the Enforcement Decree recognises a fixed share of the payment as expenses for each kind of income. That is why the withholding rate is commonly quoted as 22% yet the money actually taken is far less.

Anyone looking at a lecture-fee or royalty statement and wondering why that particular amount was withheld. If the statement matches the calculator, all is well; if it does not, the payer has applied the wrong expense rate or treated the payment as a different kind of income, and it is worth querying.

It also matters for people who accumulate several such payments in a year. Once other income amount exceeds ₩3 million in a year, withholding is no longer the end of it: the income must be combined with your other income and filed the following May. Looking only at the tax withheld on each payment leads to a missed filing, so use the calculator to check whether the annual total crosses that line.

The deemed expense rates come from 소득세법 시행령 제87조. Personal-service fees such as lecture, manuscript and consulting fees, and payments for transferring goodwill, get 60%; prizes from a public-interest foundation approved by the competent authority and prizes in ranked competitions get 80%; sales of paintings, calligraphy and antiques get 90% (80% on the part above ₩100M, or 90% if held for 10 years or more). Art and antiques are taxed only when a single piece sells for ₩60M or more, and works by a Korean artist alive on the date of sale are excluded (시행령 제41조제14항). Income with no recognised expenses, such as lottery winnings, gets 0%, so the whole payment is taxable.

The calculation has three steps. Subtract the expense share from the payment to get the other income amount. If that amount is ₩50,000 or less, the de minimis rule in 소득세법 제84조 applies and there is no tax. Above it, multiply by the 20% withholding rate in 제129조제1항제6호 to get income tax, then add 10% of that as local income tax. Measured against the income amount, that is 20% income tax plus 2% local tax, 22% in all. If the year's other income amount is ₩3 million or less, 제14조제3항제8호 lets you settle with withholding alone; above that, it joins your comprehensive income.

Take the calculator's default, a lecture fee of ₩1,000,000. The 60% expense rate removes ₩600,000, leaving an other income amount of ₩400,000. Income tax at 20% is ₩80,000, local income tax at 10% of that is ₩8,000, so ₩88,000 is withheld and ₩912,000 reaches you, 8.8% of the payment. If the same ₩1,000,000 were a public-interest foundation prize, the 80% expense rate would leave ₩200,000 of income, the tax would be ₩44,000, and the effective rate would fall to 4.4%.

Small payments carry no tax at all. A lecture fee of ₩125,000 leaves exactly ₩50,000 after expenses, which hits the de minimis threshold, so nothing is withheld. At the other end, a ₩10,000,000 fee leaves ₩4,000,000 of income, above the ₩3 million line. ₩880,000 is withheld, but that is not the end: the income must be filed together with your other income the following May.

The first is hearing "22% is withheld" and applying it to the whole payment. The rate attaches to the income after expenses, so on a lecture fee it comes to 8.8% of the payment. The second is measuring the ₩3 million threshold against gross receipts. The test is the income amount after expenses, so for lecture fees the money received has to be much larger before filing is required. The third is settling with withholding automatically whenever you are under the threshold. If your comprehensive income tax rate is low, electing to file can bring back some of the tax withheld.

The fourth is leaving the deemed rate in place when your actual expenses were higher. With documentation, actual expenses can be claimed instead. The fifth concerns goodwill payments: a payment for transferring goodwill is other income, but where the shop lease is transferred with it or the whole business is sold, the treatment can differ, so large amounts deserve professional review. Paintings and antiques also differ from other kinds in that they are taxed separately regardless of amount.