In South Korea, the payment deadline for October 2026 value-added tax (VAT) advance tax notices is Monday, November 2. By contrast, corporations required to file preliminary VAT returns must complete their filing and payment by Monday, October 26. The deadlines differ by business category because South Korea's National Tax Service (NTS) separately extended the payment deadline for advance tax notices this year.
This schedule is based on the official guidance issued by the NTS on October 5,The two dates apply to different groups of businesses. Most corporations must file their preliminary VAT returns and pay the corresponding tax by October 26. However, individual general VAT taxpayers and small corporations subject to advance tax notices have until November 2 to pay the amount stated in their notices.
| Category | Preliminary VAT Return | Advance VAT Tax Notice |
|---|---|---|
| Main taxpayers | General corporate businesses | Individual general VAT taxpayers and small corporations |
| Procedure | File a return, then pay | Pay the amount stated in the notice |
| 2026 deadline | October 26 (Monday) | November 2 (Monday) |
| Is filing required? | Generally yes | Generally no |
| What to check | Sales, purchases, and VAT payable | Whether an advance notice applies and the assessed amount |
For this purpose, a small corporation is one whose total value of taxable supplies during the preceding tax period, from January 1, 2026, through June 30, 2026, was less than KRW 150 million.
The reporting period covered by the current preliminary VAT return for general corporate businesses is July 1 through September 30, 2026.
Why Was the Advance VAT Payment Deadline Extended to November 2?
The NTS extended the payment deadline for advance VAT tax notices across the board to the end of October 2026, taking into account possible delays in delivering notices due to the concentration of public holidays in early October, including National Foundation Day and Hangeul Day (Korean Alphabet Day).
However, the extended deadline of October 31 falls on a Saturday. As a result, the actual payment deadline moves to the following Monday, November 2.
The sequence of dates makes the distinction easier to understand:
October 26 (Monday): Deadline for corporations required to file preliminary VAT returns and make the corresponding payments.
October 31 (Saturday): Extended reference date for payments under advance VAT tax notices.
November 2 (Monday): Actual payment deadline for taxpayers subject to advance VAT tax notices.
Therefore, November 2 is not a universal VAT filing deadline for all businesses in South Korea. Only the payment deadline for advance tax notices was extended; the preliminary VAT return filing deadline was not extended across the board.
Can Individual Business Owners File a Preliminary VAT Return Instead of Paying the Advance Notice?
Individual general VAT taxpayers who are subject to advance tax notices generally need only pay the assessed amount by November 2. However, even businesses that receive an advance notice may choose to file a preliminary VAT return if their sales have declined substantially or they qualify for an early VAT refund.
According to the NTS, a preliminary return may be filed when either of the following conditions is met:
Sales revenue or VAT payable for July through September 2026 is less than one-third of the corresponding amount for the preceding tax period.
Circumstances qualifying the business for an early VAT refund have arisen.
If an eligible business files a preliminary VAT return, its existing advance VAT assessment is canceled.
For example, a business owner who chooses to file a preliminary return because of declining sales should not simply wait until the November 2 advance-notice payment deadline. The preliminary return must be filed by October 26.
In other words, even among individual general VAT taxpayers, the required procedure depends on whether the business pays the amount stated in its advance notice or files a preliminary return reflecting its actual business performance.
How Is the Advance VAT Tax Notice Amount Calculated?
As a general rule, the advance VAT assessment equals one-half of the VAT paid for the preceding tax period. This differs from calculating VAT by filing a new return based on sales in the current quarter.
For example, suppose the VAT paid for the preceding tax period was KRW 2 million.
Advance VAT calculation example — author's calculation
Based on VAT payments of KRW 2 million in the preceding tax period, the advance VAT assessment would be KRW 1 million.
The actual amount payable should be verified against the notice issued by the NTS or the amount displayed in Hometax, South Korea's online tax administration service.
How to Check Your Advance VAT Notice in Hometax
Even if you have not yet received a physical advance VAT notice, you can check whether you are subject to the assessment and view the assessed amount through Hometax. You should not assume that you are exempt from payment simply because a notice has not arrived.
After logging in to Hometax, follow these steps:
1. Go to Tax Filing (세금신고) → VAT Filing (부가가치세 신고).
2. Under Filing Assistance Data Inquiry (신고도움 자료 조회), select Advance Tax Notice/Assessment Eligibility Inquiry (예정고지(부과) 대상자 조회).
3. Check whether you are subject to an advance VAT tax notice.
4. Open Advance Tax Notice/Assessment Amount Inquiry (예정고지(부과) 세액 조회) to confirm the actual assessed amount.
You can also check through My Hometax (나의 홈택스) → Payments and Outstanding Taxes (납부·체납) → Tax Notice History (고지내역).
Individual business owners may also call the NTS automated telephone service at 1544-9944 to check their advance VAT assessment after completing identity verification.
Payments can be made through Hometax or Sontax, the NTS mobile tax service. According to the NTS, electronic tax payments are available from 7:00 a.m. to 11:30 p.m.
Special Payment Deadline Extension to December 28, 2026
Some businesses affected by specific circumstances may qualify for a payment deadline later than the standard October 26 or November 2 deadlines.
The NTS announced that it would automatically extend the payment deadline to Monday, December 28, 2026, for eligible businesses in areas affected by heavy rainfall and qualifying businesses experiencing difficulties due to the prolonged corporate rehabilitation proceedings involving Homeplus, a South Korean retail company.
This measure extends the payment deadline. It does not mean that businesses required to file preliminary VAT returns may omit the filing itself.
Businesses can check whether they qualify for the extension through Integrated Filing Data Inquiry (신고자료 통합조회) in the VAT filing section of Hometax.
What Should Businesses Check Before the October 2026 VAT Deadlines?
The first thing to confirm is not merely whether the business is registered as an individual business or a corporation, but whether it is actually subject to preliminary VAT return filing or an advance VAT tax notice.
General corporate businesses should first check the October 26 filing and payment requirements. Individual general VAT taxpayers and small corporations should check their advance-notice status through Hometax.
Even if a business is subject to an advance notice, it must separately observe the preliminary filing deadline if it chooses to file a return because of declining business performance or eligibility for an early refund. Businesses qualifying for an automatic payment deadline extension should also verify their individual notifications and the extension status displayed in Hometax.
For South Korea's October 2026 VAT schedule, identifying your applicable filing and payment category is more reliable than remembering a single deadline.
*Note: This article is provided for reference to help readers understand market trends and does not constitute an investment recommendation concerning any particular security or asset. Readers are responsible for their own final decisions and investment risks.*