2026 South Korea Substitute Holidays and Business Days

The Korea Astronomy and Space Science Institute page reproducing the Korea AeroSpace Administration's 2026 calendar summary lists 70 public holidays on the government-office calendar and 118 days off for a five-day-workweek organization. That summary was published on June 30, 2025 and is a calendar-production baseline, not a substitute for a later legal or workplace update.

The same official summary identifies four three-day periods created by substitute holidays in 2026. These dates help with planning, but an operational deadline should still be checked against the current regulation and the applicable organization calendar.

• March 2: substitute holiday following March 1 Independence Movement Day.
• May 25: substitute holiday following Buddha's Birthday on Sunday, May 24.
• August 17: substitute holiday following Liberation Day on Saturday, August 15.
• October 5: substitute holiday following National Foundation Day on Saturday, October 3.

The 2026 annual calendar summary predates an amendment to the Public Holiday Regulation. The current National Law Information Center text shows an effective date of May 11, 2026 and includes Labor Day on May 1 in the government-office public-holiday list.

Because the legal text changed after the annual summary was published, do not infer a final holiday count from the older total alone. Use the annual summary for its stated baseline and the current regulation for the rule now in force.

Start with the calendar dates in the period, remove the non-working weekdays used by the organization, then remove applicable public holidays and add any company-specific closure dates. Apply the contract's start-date and end-date inclusion rules last so day 0 and day 1 are not confused.

• Choose the country and year that govern the deadline.
• Set the organization's weekend rule instead of assuming Saturday and Sunday.
• Exclude public holidays only when the selected rule makes them non-working days.
• Add regional, bank, school, company, or contract-specific closures manually.
• Confirm whether the start date and end date are included in the count.

Assume a South Korea schedule starts on Friday, February 27, 2026, excludes Saturdays, Sundays, and applicable public holidays, and does not count the start date. The weekend is skipped, and the March 2 substitute holiday is also skipped. The first counted business day is Tuesday, March 3, so the fifth counted business day is Monday, March 9.

A contract that includes the start date, uses a different weekend, or does not recognize the substitute holiday will produce a different result. Record those assumptions beside the calculated date.

National public-holiday data does not automatically represent every local closure, bank schedule, school calendar, employer policy, exchange calendar, or contract definition. Temporary holidays and provider-specific operating days can also change after a planning page is reviewed.

DeadlineDays is a planning tool, not an official calendar or legal interpretation. Verify binding dates with the current government source and the organization responsible for the deadline.