Korea Freelance Tax: The 3.3% Withholding, the May Filing, and Getting Your Refund

The 3.3% withholding is an advance, not the final tax

When a Korean company pays you for freelance work — writing, design, development, translation, tutoring, consulting — it is generally required to withhold tax from each payment. For personal-service business income (saeop sodeuk, 사업소득) the standard withholding is 3.3%: 3% national income tax plus 0.3% local income tax.

This is the single most misunderstood number in freelance taxation in Korea. The 3.3% is not your final tax rate. It is an advance payment, held by the National Tax Service against the tax you will owe once your actual income and expenses are calculated.

Your real tax is worked out at the annual filing stage. Because Korea’s income tax is progressive and freelance income gets business-expense deductions, most freelancers are over-withheld — which is exactly why filing matters: the overpaid amount is refunded.

The May comprehensive income tax return

Freelance business income is reported through the comprehensive income tax return (jonghap sodeukse, 종합소득세), filed once a year for the previous calendar year. The window is May 1 to May 31; for 2026 the deadline shifts to June 1 because May 31 falls on a Sunday.

The filing is done on Hometax (hometax.go.kr), Korea’s tax portal, using your foreign registration number as the login identity. Your clients report the payments and withholding to the NTS, so Hometax usually pre-loads the 3.3% payment records — you verify the amounts, add your expenses and deductions, and the system calculates whether you are owed a refund or owe more.

The local income tax portion is handled separately through the local tax portal, with a data-transfer link from Hometax — the same 10% local surtax structure described in our local income tax guide.

How the refund works

A refund occurs when the 3.3% withheld during the year is larger than your final calculated tax.

Your final tax is based on your net profit — gross freelance income minus business expenses. For most freelancers the largest deduction is a government-set simplified expense ratio (dansun gyeongbiyul, 단순경비율), which lets you deduct a fixed percentage of gross income as deemed business expenses without collecting receipts. The percentage depends on your business code and income level.

Because the expense ratio plus the basic personal deduction often bring taxable profit below what the 3.3% withholding assumed, many low- and mid-income freelancers get most of the withheld amount back. If you never file, that overpaid amount simply stays with the government — it is not returned automatically.

If your income is higher or your actual expenses exceed the simplified ratio, you can choose a different expense method, but the thresholds and rates are set by the NTS by business code, so check the current figures rather than borrowing another freelancer’s numbers.

Business registration and obligations

Before or shortly after you start regular freelance work in Korea, you should register as a sole proprietor (gaein saeopja, 개인사업자) with the National Tax Service. Registration affects how clients withhold and how you file VAT.

Two obligations to keep straight:

• VAT — once your annual turnover crosses the relevant threshold, you register for VAT and file twice a year (July and January). Below the threshold the simplified rules apply.
• Social insurance — freelancers are not covered by an employer’s contributions; you enrol in national pension and health insurance in your own right, which is separate from tax but affects your net position.

Your registration number is also how clients issue you proper payment certificates, which in turn lets Hometax pre-load your income at filing time. The broader filing and deduction picture is covered in our global income tax return guide and the taxes in Korea overview.

What does not apply to freelancers

Two things people expect to help often do not:

• The 19% flat tax is for employees only. The foreign-employee flat rate applies to employment income (geullo sodeuk, 근로소득); it does not apply to freelance business income. Freelance income is reconciled through the progressive business-income calculation.
• Year-end settlement is not your route. If you also hold a salaried job, your employer runs the year-end settlement for your salary, but the freelance income sits outside it and still goes into the May comprehensive return.

If you have both salary and freelance income, both go into the May return combined — which can reduce the refund or create additional tax depending on your total. Keep every withholding certificate (woncheon jing-su yeongsu-jeung, 원천징수영수증) from each client through the year.

Note — withholding rates, expense ratios, thresholds and deadlines are set by the NTS and revised periodically. This article is general information as of August 2026 and is not tax advice — verify the current rules on Hometax or the National Tax Service, or consult a qualified tax professional.