Individual Income Tax

The deadline

Global income tax is filed and paid between 1 and 31 May of the following year. Taxpayers subject to the compliance verification requirement file by 30 June.

What gets combined

The following are added together and taxed under a single rate schedule:

• Business income — sole proprietors, freelancers subject to 3.3% withholding, delivery, lecturing, services
• Employment income — still combined if you have other income, even after year-end settlement
• Interest and dividend income — combined above KRW 20 million per year
• Pension income
• Other income — royalties, lecture fees, prizes

Each source may look lightly taxed on its own, but combining them pushes you into a higher bracket. This is the most common reason a May bill is larger than expected.

Who should have their position reviewed

Freelancers subject to 3.3% withholding

That 3.3% is tax paid on account, not a final settlement. With expenses properly reflected, a refund is common; where income is high, additional tax arises instead. Keeping expense records translates directly into tax saved.

Both business and employment income

A year-end settlement at your employer does not remove the May filing obligation if you also have business income.

Residential rental income

Where rental receipts are KRW 20 million or less per year, you may choose between separate and global taxation. We calculate both and compare.

Multiple business locations

Results are aggregated, and we check whether a loss at one location can be offset against income at another.

Bookkeeping tier changes the tax

Keeping books lets you deduct expenses as actually incurred. Filing on an estimated basis allows only the standard expense ratio for your industry, which often produces a higher tax bill, plus a penalty for failing to keep books.

Above certain revenue thresholds, double-entry bookkeeping becomes mandatory. The thresholds differ by industry group — see the table on our fees page. If you are unsure which tier applies to you, we will confirm it at the consultation.

November interim prepayment

If last year’s tax exceeded a set amount, an interim prepayment notice arrives in November. Where this year’s results are materially lower, filing an estimated interim return reduces the amount.

After filing

If tax was overpaid in any of the last five years, it can be recovered through a refund claim. We review prior filings as well.

For foreign residents

Whether you are taxed on Korean-source income only or on worldwide income depends on your residency status, which turns on facts rather than visa type alone. If you have income outside Korea, or moved to or from Korea during the year, tell us at the consultation — it determines the scope of the return.