Get through year-end tax settlement

Every January and February, Korean employees settle their previous year's income tax with their employer through 연말정산. For a foreign employee, the process carries one decision that Korean colleagues do not face — whether to be taxed under the progressive brackets like everyone else, or to opt in to a flat 19% rate that trades most deductions for a simpler bill. Choosing without running both numbers is, by a distance, the most expensive mistake in Korean paperwork.

How it actually goes at my company

I don't run the settlement myself. Our foreign employees' year-end tax is handled by an outside tax and labour office, and my job is getting their documents to that office on time. Two things I have seen every year are worth knowing before January.

Flat rate or progressive is not the same for everyone. Even among staff on the same visa at the same company, some are settled under the single flat rate and some under the normal progressive rates, depending on their situation. Don't assume a colleague's result tells you anything about yours; ask which method was applied to you.

The surprise is usually a bill, not a refund. The most common problem I deal with is not a missing refund but an employee who owes additional tax in February and didn't expect it. If your February payslip shows a deduction larger than usual, that is the settlement, and it is worth asking the office to walk you through the calculation.

The choice: flat rate or progressive

The Restriction of Special Taxation Act offers a qualifying foreign employee an election to be taxed at a flat 19% on their total Korean employment income, in place of the standard progressive brackets. The flat rate carries a trade-off: no personal deductions, no dependant credits, no housing or credit-card or medical-expense deductions, no monthly-rent credit. What you see is what you pay — 19% on the gross, plus the 10% local income surtax on that.

For a moderate salary with a spouse, children and a Korean rent bill, the progressive path with deductions is usually cheaper. For a high salary, especially a first-year assignee with limited Korean-side deductions, the flat rate is often meaningfully cheaper. There is no shortcut — run both numbers.

The progressive brackets

2026 rates on national income (with a 10% local income surtax on top):

• Up to ₩14,000,000 — 6%
• ₩14,000,001 – ₩50,000,000 — 15%
• ₩50,000,001 – ₩88,000,000 — 24%
• ₩88,000,001 – ₩150,000,000 — 35%
• ₩150,000,001 – ₩300,000,000 — 38%
• ₩300,000,001 – ₩500,000,000 — 40%
• ₩500,000,001 – ₩1,000,000,000 — 42%
• Above ₩1,000,000,000 — 45%

These apply to taxable income after Korean employment-income deduction and personal deductions. The effective rate paid is typically lower than the top marginal rate — the progressive schedule is applied bracket by bracket.

Deductions foreign employees can use on the progressive path

Not exhaustive; the practical list a foreign employee on progressive rates should be tracking includes:

• Personal and dependant deductions for spouse and eligible dependants living in the household or supported abroad, on evidence.
• National Pension and health-insurance contributions — deducted automatically from the tax base.
• Credit-card and debit-card spending above a threshold of your annual income — a credit up to a cap.
• Cash receipts (현금영수증) for cash purchases, subject to the same aggregate cap as cards.
• Monthly rent — a credit for rent paid on a residence up to a stated ceiling, subject to income limits and evidence.
• Medical, education, insurance premium, donation credits — each with its own rules and evidence requirements.
• Housing savings and personal pension contributions in eligible schemes.

Most of these are pre-populated in the Hometax Simplified Year-End Settlement service, which pulls data direct from banks, card companies, hospitals and pharmacies. Anything not pre-populated needs paper evidence.

The Hometax workflow

1. In mid-January, log in to Hometax with your certificate or Simple Login. The Year-End Tax Settlement Simplified service opens on a set date announced by NTS.
2. Consent to the data collection so the portal can pull card, medical, insurance and other data on your behalf.
3. Download the resulting PDF summary and hand it to your employer's payroll team, or upload it directly if the employer uses a Hometax-linked payroll platform.
4. Fill in what is missing — foreign-issued documents, dependants supported abroad, rental credit if the landlord is not registered — and provide supporting evidence.
5. Employer runs the calculation, applies the flat-rate election if you have opted in, and reflects the refund or additional bill in February or March payroll.

Where people overpay

• Defaulting to the flat rate because "it's simpler". On a mid-range salary with dependants and rent, this can leave several million won on the table.
• Missing the rental credit. Requires the landlord's cooperation on evidence and, historically, some risk of the landlord being invoiced on undeclared rental income — negotiate this into the lease at signing.
• Not collecting cash receipts. Cash spending without 현금영수증 does not count toward the card-and-cash deduction.
• Dependants abroad not declared. A qualifying supported parent or child in your home country can be claimed — many foreign employees do not know.
• Assuming last year's flat-rate benefit repeats. Eligibility windows and rates have changed; re-check every year.

Common questions

What if I joined mid-year, or left mid-year?

Settlement is on the actual Korean employment period in the calendar year. Prior overseas income of the same year is not aggregated for Korean tax purposes on the standard employee return, subject to residency rules.

What about my home-country tax return?

Korean payroll tax and your home-country obligation are separate. Many countries have tax treaties with Korea that credit tax paid in Korea against your home-country liability — the treaty text is the authority, not any general rule of thumb.

Do I need a Korean accountant?

For a standard salary at one employer with no unusual items, no. For multiple income sources, stock-based compensation, a mid-year transfer or a significant home-country tax overlap, a licensed Korean tax preparer's time is well spent. The tax office (세무서) itself is listed in which office handles what, and the vocabulary guide covers the Korean terms on the Hometax screens. A related withholding decision comes up again if you eventually claim the pension lump-sum refund on departure.

What if my refund does not arrive?

It flows through payroll, not from NTS to your account directly. Check the March payslip; if the settlement figure is missing, ask HR before assuming a Hometax error.