[Korean Tax Knowledge Series 1-C] Prevent tax overpayment with a 3-minute year-end tax adjustment check

Missing just three lines on your payslip can lead to overpayment and refund delays.

The key is non-taxable income, deductions, and withholding tax – the three main areas.
Employees settle once a year (January-February), and omissions can be corrected in May.
Local income tax is an additional 10% of the national tax.

Year-end tax settlement: The process of recalculating taxes withheld throughout the year to determine final refunds or additional payments.
Payslip: A statement showing monthly salary, deductions, and non-taxable income. It's the starting point for identifying errors.
Non-taxable income items: Portions of income not subject to tax (e.g., meal allowance up to ₩200,000/month).
Income/Tax Credits: Reducing tax liability through expenses like insurance, medical, education, and rent, as well as tax deductions.
Local income tax: A local tax levied at an additional 10% of the calculated national tax amount.

Was the non-taxable meal allowance of ₩200,000/month applied for all previous months?
Are the details for your spouse, children, and dependents up to date?
Are documents for rent, insurance, medical, education, and donations reflected without omissions?
Did you join, leave, or switch jobs this year, and is the combined income calculation accurate?
👉 If you answered yes to three or more of these, a refund is likely.

Depending on the application of non-taxable income and deductions, the refund amount can vary from tens of thousands to hundreds of thousands of won.
If items are missed during the company's settlement, you can claim a refund by supplementing them through the May comprehensive income tax filing.
You must consider the additional 10% local income tax to accurately assess your actual tax burden.

Scope of application: Missing non-taxable meal allowance vs Omission in combined income calculation for mid-year hires
Key difference: Whether the monthly non-taxable amount was applied correctly / Accuracy of combined income from multiple employers
Actual impact: 6 months of missing non-taxable benefits leading to increased taxable income and overpayment. For mid-year hires, omissions in combined income can be corrected in May for a refund.

Obtain your payslips for the past 12 months and your Withholding Tax Receipt.
Check the monthly application of non-taxable items (meal allowance ₩200,000/month, private vehicle allowance, etc.).
Gather receipts and payment certificates for rent, insurance, medical, education, and donations, and create a summary.
Compare the details reflected in your company's settlement with your own records, and request corrections for any omissions.
If corrections are difficult or if there are significant omissions/job changes, prepare for a refund through the May comprehensive income tax filing.

A: Annual salary ₩45 million, 6 months of missed non-taxable meal allowance → After reapplying the non-taxable benefit, a refund of national and local taxes is possible.
B: Hired in August, prior employer's withholding data not reflected → Combined and deducted through May comprehensive income tax filing → Refund.

“The company handles everything automatically” → Omissions are frequent, so personal verification is necessary.
“Non-taxable items are processed automatically” → Limits (₩200,000/month) and monthly application may be omitted.
“There’s no separate local tax” → Local income tax is levied at 10% of the national tax.

Tax Info