Korea tax guide

Business Income vs Other Income in Korea for Foreigners

By Korea Tax Guide Editorial Team | Last reviewed: August 11, 2026 | Last updated: August 11, 2026

3.3% Freelancer Tax Intermediate

Summary: How foreigners in Korea can distinguish recurring business income from one-off other income, and why the classification affects expenses, withholding, records, and May tax filing.

Who this guide is for

Quick Answer

Korea generally looks at the real nature and repetition of the activity, not only the label used by the payer. Repeated independent services commonly point toward business income, while a genuinely occasional payment may be other income. The classification can change withholding, deductible-expense treatment, record keeping, and how the amount is included in a May global income tax return.

Key points

Step-by-step explanation

Look beyond the payer’s label

Start with what you actually did. Record whether the service was offered repeatedly, whether you found your own clients, supplied your own tools, bore costs or risk, and intended to earn continuing profit. A payer’s memo, platform category, or withholding percentage is useful evidence but does not replace the factual analysis.

Compare recurring and occasional activity

The NTS foreigner guide uses lectures as a practical example: a payment under employment can be wage income, a one-off lecture can be other income, and repeated freelance lectures can be business income. The same logic can be relevant to translation, tutoring, consulting, performance, and content work, but each activity needs its own facts.

Match expenses to the correct category

For business income, organize actual revenue and supported necessary expenses or determine whether an official expense-rate method is available. For other income, check the specific statutory expense treatment for that payment type. Do not move expenses between categories merely to produce a better result.

Reconcile the annual return

Download payer statements and Hometax income data, then compare them with bank receipts and contracts. A May global income tax return may combine business income, other income, salary, interest, dividends, and other categories. Correct classification comes before the refund or balance-due calculation.

Keep immigration and tax questions separate

Reporting income does not retroactively authorize work under a visa, and a visa restriction does not make received income tax-free. If either point is unclear, obtain immigration and tax advice from qualified professionals in the respective fields.

Documents you may need

Common mistakes

When should you ask a tax professional?

Ask a qualified tax professional if you have income from several countries, business income, unclear tax residency, treaty questions, missing documents, late filing concerns, or a visa situation that depends on tax records. This site explains general patterns only and cannot review your personal facts.

FAQ

Is one paid lecture business income or other income?

A genuinely occasional lecture may be other income, while repeated lectures provided independently can point to business income. Employment-contract lectures can instead be wage income.

Does 3.3% withholding decide the category?

No. Withholding is evidence of how the payer reported the amount, but the underlying facts and legal classification still matter.

Can I deduct the same expenses under both categories?

Do not assume so. Necessary-expense rules and evidence can differ by category and by the type of payment.

Do I still file if tax was withheld?

Possibly. Withholding is usually a prepayment, and the income may need to be reconciled in a May return with your other income and allowable expenses.

Official Sources to Verify

Tax rules and filing procedures in Korea may change depending on your visa status, income type, tax residency, and the tax year. Before making a tax decision, always verify your situation with official sources or a qualified professional.