Comprehensive income tax — filed in May
This page is machine translated from Ieumi's guide written in Korean. If the meaning is confusing, please look at the Korean original text. View original text (Korean)
If you earned money outside of a company, self-report it from May 1 to 31. If 3.3% was withheld from your payment, this applies to you.
Deadline
Every year from May 1 to May 31.
📌 Key points
If 3.3% was withheld from your payment, you were treated not as an employee but as someone hired for a task. That income is not settled through year-end settlement and must be separately reported in May. Those who received salary from two or more companies, or who have other income, also combine and report it in May.
📍 Where to go
The tax office with jurisdiction over your address. National Tax Service consultation: 126; English-language consultation for foreigners: 1588-0560.
The screen is in Korean. The tax office's civil service center can help you.
⚠️ Things to watch out for
Failing to report incurs a penalty tax. Also, without an income report, you cannot obtain an Income Amount Certificate — this becomes an even bigger problem for those who need to prove income for naturalization or visa extension.
❗ What happens if you don't
If you don't file, a failure-to-file penalty tax applies; if you underpay, an underreporting penalty tax applies; if you pay late, a late payment penalty tax applies.
See also
Basis
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This content was checked on 2026-09-10.