If you're a resident with interest, dividend, business, wage, pension, or other income, you must in principle file and pay comprehensive income tax between May 1 and May 31 of the following year. If wage income is your only income and it was already settled at year-end, no separate filing is needed — but if you also have freelance income, rental income, or similar, you must combine and file everything in May.
You can file electronically via Hometax (PC) or Sontax (mobile app), or in person at a tax office. Register on Hometax using your alien registration number, then log in with a certificate or simplified authentication to proceed.
Common cases requiring a May filing
What happens if you skip filing when required
Failing to file when required triggers a non-filing penalty (20% ordinary, 40% for fraudulent under-reporting) plus a late-payment penalty (0.022% per day, roughly 8% annually). If you're unsure whether you need to file, checking with the National Tax Counseling Center (126) or a tax professional beforehand is far cheaper than guessing wrong.
Frequently Asked Questions
Related Topics
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