Tax in South Korea

Who is the tax authority?

The National Tax Service (Gukse-cheong, NTS) is Korea's principal tax authority. It was established in 1966 as an external organ of the Ministry of Economy and Finance. NTS operates through six Regional Tax Offices and roughly 130 District Tax Offices nationwide.

NTS administers the Income Tax Act (Sodeukseosebeop / 소득세법), the Corporate Tax Act, the Value Added Tax Act, the Inheritance and Gift Tax Act, and the Comprehensive Real Estate Tax Act. Korea Customs Service handles customs and excise. Local government tax administrations collect the Local Resident Tax that piggybacks on national income and corporate tax.

Credentialed tax professions include Certified Tax Accountants (semu-sa / 세무사) regulated under the Certified Tax Accountant Act and Certified Public Accountants regulated under the CPA Act. The Korean Institute of Certified Public Accountants (KICPA) and the Korean Association of Certified Public Tax Accountants (KACPTA) are the principal professional bodies.

What is the tax year and when are returns due?

Korea's tax year matches the calendar year (1 January to 31 December). The personal Comprehensive Income Tax return is due 31 May of the following year. Companies file the Corporation Tax Return within three months of their fiscal year-end.

The Yeonmal-Jeongsan (Year-End Tax Settlement / 연말정산) is the primary mechanism for salaried employees. Employers reconcile the full year's withholding against actual liability each February, generating a refund or a top-up processed through the February or March payroll. Salaried filers whose income is fully covered by Yeonmal-Jeongsan and who have no other reportable income do not file a separate Comprehensive Income return.

Who counts as a Korean tax resident?

Under Article 1-2 of the Income Tax Act, a person is a Korean tax resident if they maintain a domicile (juso / 주소) or a residence (geoso / 거소) in Korea for one year or more. Domicile is the place where the individual maintains family-life relationships and the centre of everyday economic interests. The one-year threshold for residency triggers retroactive treatment of the period of presence.

Korea operates a four-tier residency framework. Residents are taxed on worldwide income. Non-residents pay tax only on Korean-source income. Short-Term Foreign Residents — foreigners who have not been a Korean resident for more than five of the last ten years — are taxed on Korean-source income plus only the portion of foreign-source income remitted to Korea, a structurally favourable position for foreign workers in their first five years. Diplomats receive specific exemptions.

Departure from Korea can trigger exit-tax exposure on substantial-shareholding positions under Articles 118-9 to 118-13 of the Income Tax Act. Treaty residency tie-breakers under Korea's bilateral DTCs apply where two jurisdictions both treat a person as resident.

Deep-dive: see expat and cross-border tax in South Korea for the practical rules around moving in or out mid-year.

What are the personal income tax rates?

Korea's Sodeukse (personal income tax / 소득세) uses an eight-bracket progressive structure. The Local Resident Tax (Jibang Sodeukse / 지방소득세) adds a 10 percent surtax on top of the national rate, bringing the effective combined top marginal rate to approximately 49.5 percent.

Key deductions include the standard personal deduction, dependant deductions, credit-and-debit-card spending deduction, education and medical-expense deductions, mortgage-interest deduction on a principal residence, and National Pension contribution deductions. The Financial Investment Income Tax (FIIT) on listed-securities capital gains has been further deferred to 1 January 2027 under the most recent legislative cycle.

Deep-dive: see self-employed tax in South Korea for how all charges stack up for freelancers.

How does corporate tax work?

Korea's Beobinse (corporate income tax / 법인세) operates on a four-bracket progressive structure introduced in the 2023 reform under the Yoon government.

The Local Resident Tax is levied at 10 percent of the national corporate tax, adding roughly 0.9 to 2.4 percentage points to the effective rate. Korea implemented the OECD Pillar Two Global Minimum Tax via amendments to the International Tax Coordination Act; the Income Inclusion Rule applies for fiscal years beginning 1 January 2024 for groups with consolidated revenue above EUR 750 million. The R&D tax credit (R&D 세액공제) provides reduced effective rates on qualifying research expenditure with sector and size differentiation. Net operating losses carry forward for 17 years — one of the longer carryforward periods in the OECD.

Deep-dive: see corporate tax in South Korea for SME vs conglomerate comparison.

What about VAT and indirect taxes?

Bugagachise (Value Added Tax / 부가가치세) is Korea's principal indirect tax. The standard rate has been a flat 10 percent since 1977 — there is no reduced or super-reduced rate tier.

Mandatory VAT registration applies from the start of taxable activity (KRW 0 threshold). A Simplified Tax Regime is available for operators with annual revenue below KRW 80 million. Cross-border digital services to Korean consumers by non-resident vendors have been subject to VAT under the Electronic Service Provider regime since 2015 for B2C digital services and expanded further in 2019. The Special Excise Tax applies to alcohol, tobacco, motor vehicles, gambling, and luxury goods.

Deep-dive: see VAT in South Korea for the B2C digital-services registration mechanics.

How are cryptoassets taxed?

Korea passed comprehensive crypto-asset taxation legislation in late 2020, but the effective date has been deferred multiple times under successive legislative cycles. The current effective date is 1 January 2027.

Deep-dive: see crypto taxation in South Korea for the VASP registration requirements under the Specific Financial Information Act.

What is the treaty network?

Korea maintains approximately 95 comprehensive Double Taxation Conventions — one of the larger bilateral treaty networks in Asia. Most treaties follow the OECD Model with Korean reservations on the credit method and on technical-services source taxation.

Korea signed and ratified the OECD Multilateral Instrument; the MLI's modifications, including the Principal Purpose Test, apply to many of Korea's covered DTCs from 2020 onward. Foreign tax-credit relief is generally claimed under Article 57 of the Income Tax Act for individuals and Article 57 of the Corporate Tax Act for corporations.

Deep-dive: see tax treaty relief in South Korea for the bilateral withholding-rate schedules.

Where does South Korea sit in the East Asia cohort?

South Korea anchors the East Asia developed-economy cohort alongside Japan, Singapore, and Taiwan. The East Asia region splits into five distinct tax archetypes:

Common pitfalls and penalties

Foreign individuals and companies regularly trip on a set of recurring traps when operating in Korea:

When should you talk to a semu-sa?

Some situations are straightforward enough to handle through NTS HometaxWTS. Others get complicated quickly:

• Your income enters the 35% bracket or higher (over KRW 88 million)
• You are a foreign worker deciding whether to elect the 19% flat rate
• Your Korean residency period is approaching the five-of-ten-year Short-Term Foreign Resident threshold
• You run a company subject to the CFC regime or transfer-pricing master-file obligations
• You have cross-border income from a treaty partner and need to claim foreign tax-credit relief
• You received an NTS notice of assessment, audit initiation letter, or back-tax query
• You hold substantial shareholdings and are considering departing Korea
• You are unsure whether VAT registration or the Electronic Service Provider regime applies to your digital business

You can find vetted Korea practitioners through the directory below.

This page is general information. It is not personal guidance for your specific situation. Tax rules change. Always check current figures on the NTS website (nts.go.kr) or with a licensed Korea practitioner before filing.