If you left your job during 2026 and were not reemployed by the end of the year, you can claim eligible income deductions and tax credits omitted when you resigned by filing a comprehensive income tax return in May 2027. However, filing a return does not automatically mean you will receive a refund. To determine whether a refund is due, you must compare the tax settled by your former employer with your final tax liability after applying additional deductions.it is important to distinguish between the tax settlement performed by a South Korean employer when an employee leaves and the additional tax return the former employee may file the following year.
1. What Happens to Your Year-End Tax Settlement When You Resign?
In South Korea, an employer settles an employee's employment income tax when paying their salary for the month in which they leave the company. This is commonly called a year-end tax settlement for a departing employee or an interim tax settlement.
A regular year-end tax settlement takes place after the calendar year ends, when employees and employers review deduction records such as medical expenses, education expenses, and credit card spending.
An interim settlement, however, takes place when employment ends. As a result, only basic deductions may be applied, while other eligible deductions may be omitted.
For example, if you resigned in June 2026, your employer would settle your income tax when paying your final salary, based on the employment income earned up to that point.
If you were unable to submit supporting documents for additional deductions during that process, you may be able to claim them through a comprehensive income tax return in May 2027.
There is an important distinction here.
Having completed a tax settlement when you resigned does not necessarily mean that every available deduction was included.
The subsequent filing process allows you to review potentially omitted deductions while taking into account the tax already settled by your former employer.
2. Who Needs to File a Tax Return in May 2027?
If you resigned during 2026 and did not join another company before the end of that year, you are responsible for filing a comprehensive income tax return if you wish to claim eligible deductions omitted from your previous settlement.
Being unemployed after resignation does not erase the employment income you earned during 2026. You can still settle taxes relating to the tax year in which that income was earned.
The appropriate procedure depends on your employment circumstances after leaving your job.
| Employment situation in 2026 | Year-end tax settlement or filing procedure |
|---|---|
| Resigned during the year and remained unemployed through December | Former employer performs an interim settlement; omitted deductions can be claimed through a May 2027 return. |
| Resigned and joined another company during the same year | New employer combines employment income from the previous employer when performing the year-end tax settlement. |
| Changed jobs during the year but previous employment income was not included | Check that employment income from both employers is combined in the following year's comprehensive income tax return. |
| All eligible deductions were already applied when employment ended | Determine whether another return is necessary based on the previous settlement and whether other taxable income exists. |
Not everyone who resigns is automatically required to file a comprehensive income tax return in May.
If your taxes were fully settled when you left, you have no additional deductions to claim, and you have no other income requiring a comprehensive income tax return, a separate filing may not be necessary.
Conversely, if you earned business income or other income subject to comprehensive income tax reporting, you must check your filing obligations separately from the question of omitted employment income deductions.
3. When and How to File Your 2026 Income Tax Return
As a general rule, comprehensive income tax returns for income earned during 2026 are filed in May 2027.
South Korea's standard statutory filing period for comprehensive income tax runs from May 1 through May 31 of the following year. However, the actual 2027 deadline should be confirmed against any extensions resulting from public holidays and the National Tax Service's instructions for that filing year.
Returns can be filed through Hometax, the online tax service operated by South Korea's National Tax Service (NTS).
May 2027: Filing Income Earned During 2026
1. Log in to Hometax.
2. Navigate to Tax Filing → Comprehensive Income Tax Return → Employment Income Return → Regular Filing.
3. Review your 2026 employment income records and previous tax settlement details.
4. Enter eligible deductions and tax relief items omitted when you resigned, and check the supporting documentation.
5. Review the calculated tax liability and whether you are entitled to a refund or must pay additional tax, then submit your return.
The actual filing screens and menu names may change depending on the filing year.
The filing category may also differ between someone who earned only employment income and someone who additionally earned business income or other types of income. It is therefore advisable to review the income information available in Hometax before selecting a filing procedure.
4. Check Your Employment Income Withholding Tax Certificate First
The employment income withholding tax certificate, known in Korean as the *Geunro Sodeuk Woncheon Jing-su Yeongsujeung* (근로소득 원천징수영수증), is a key document for determining how much tax was settled when you left your employer.
This certificate shows your employment income, deductions, final assessed tax liability, and taxes already withheld.
Before filing in May 2027, check the following information:
Whether all employment income paid to you during 2026 is accurately reflected.
Which income deductions and tax credits your employer applied when you resigned.
The amount of your final assessed tax liability.
Whether additional tax was collected or a refund was issued when you left.
You can request the withholding tax certificate from your former employer. Once the employer's submitted income payment statement is reflected in Hometax, you may also be able to review the relevant information there.
However, the certificate issued directly by your employer and the information available through Hometax may not become available at the same time.
If the necessary records are missing while you prepare your 2027 return, contact your former employer to request the withholding tax certificate and confirm whether the income payment statement has been submitted.
5. How to Calculate Whether You Will Receive a Tax Refund
The amount of any refund depends on the difference between the income tax already paid and the final assessed tax liability after eligible additional deductions are applied.
There is no fixed refund amount simply because you resigned during the year. You must also account for any refund already received when you left your job.
The following is a hypothetical example illustrating the calculation principle.
Hypothetical Example: Author's Calculation
The calculation considers these figures:
Income tax ultimately paid in advance.
Final assessed tax liability after applying additional deductions.
The resulting refund calculation.
The illustrative refund amount.
In this example, the final assessed income tax falls to KRW 300,000 after additional deductions are applied, resulting in a calculated income tax refund of KRW 200,000.
Local income tax is separate. The actual refund depends on the information reported and the final tax calculation.
If no income tax was previously paid, or if the additional deductions do not reduce the final assessed tax liability, there may be no refund.
When assessing a potential refund, what matters is the actual reduction in tax liability, not simply the amount of expenses eligible for deductions.
6. Can You Deduct Expenses Paid After Leaving Your Job?
The deductions available to employees who resign during the year may depend on when expenses were incurred and whether they relate to a period of employment.
In particular, credit card spending deductions and certain special tax credits are subject to restrictions associated with the period during which employment services were provided.
For example, suppose you resigned in June 2026 and remained unemployed from July through December. You should not assume that every expense incurred after resignation qualifies for the same deductions as expenses incurred while you were employed.
On the other hand, some deductions are assessed using annual eligibility requirements. It would therefore also be incorrect to assume that every deduction is automatically limited to expenses incurred before your resignation date.
When reviewing deduction records in May 2027, distinguish between two types of requirements.
First, determine whether the deduction applies only to qualifying expenses incurred during the period of employment.
Second, check whether eligibility is determined by annual income, family relationships, qualifying dependents, or other conditions that apply to the tax year as a whole.
The fact that an expense appears in South Korea's simplified year-end tax settlement records does not, by itself, establish that the entire amount is deductible.
7. Can You Receive Another Refund If You Already Got One When You Resigned?
Even if you received a refund when you resigned, you may be entitled to an additional refund through your May filing if eligible deductions were not included in the original settlement.
However, this does not mean receiving the same tax refund twice.
The process involves comparing the tax liability calculated when you resigned with the revised final liability after additional deductions, while accounting for amounts already settled.
For example, if your former employer applied only basic deductions when you left, adding other eligible deductions could reduce your final tax liability.
Conversely, if all deductions were already included and you ultimately have no income tax liability, there may be no additional tax to refund.
8. What If You Miss the May 2027 Filing Period?
Missing the regular filing period does not necessarily mean permanently losing the opportunity to recover overpaid tax.
If the tax previously reported or settled exceeds the amount you were legally required to pay, you may be able to request a correction under the applicable statutory requirements and deadlines.
In South Korea, this procedure is called a *Gyeongjeong Cheonggu* (경정청구), or request for correction. It allows a taxpayer to ask the tax authorities to correct an excessive tax declaration or payment.
However, the applicable correction period and its starting date must be checked according to your filing circumstances. Any refunds already received and deductions previously claimed must also be reviewed.
It is therefore advisable to use the regular May 2027 filing period first. If you miss it, review your previous tax records and determine whether you qualify to submit a request for correction.
9. What Should You Prepare Before May 2027?
As of October 2026, the comprehensive income tax filing period for income earned during 2026 has not yet begun.
This is a useful time to prepare your employment income records and supporting documentation for deductions you may claim in May 2027.
Start by obtaining your 2026 employment income withholding tax certificate from your former employer. Then confirm whether you were reemployed during 2026 and whether you earned any other income that may require a tax return.
Next, review which deductions were already applied when you resigned. If you discover omitted deductions, check the specific eligibility requirements before including them in a return.
In May 2027, retrieve your 2026 income records through Hometax, compare them with your previous tax settlement, apply any additional eligible deductions, and review the resulting final tax liability.
You do not need to assume that leaving your job means losing the opportunity to complete your year-end tax settlement. The important questions are how much tax you already paid during 2026 and whether you still have eligible deductions that were not previously applied.