“How many working days are in this month?” comes up every month for payroll, project schedules and delivery dates. Counting by eye makes it easy to miss public holidays and substitute holidays, so I ran Hyuilmoa’s holiday data month by month for 2026 and 2027.
How working days are counted
The rule is simple: take the Monday-to-Friday weekdays in the month and subtract the public holidays (substitute holidays included) that fall on a weekday.
- Working days = weekdays in the month - public holidays that fall on a weekday
- A holiday that lands on a Saturday or Sunday is already a day off, so it is not subtracted again.
- A substitute holiday moves the day off to a weekday, so that day is subtracted.
Results for 2026 and 2027
These values come from running the site’s holiday data month by month. Weekday and holiday counts come from the same calculation; no number was edited by hand.
| Year | Weekdays | Holidays on weekdays | Working days |
|---|---|---|---|
| 2026 | 261 | 16 | 245 |
| 2027 | 261 | 15 | 246 |
Both years have the same number of weekdays. One fewer holiday falls on a weekday in 2027, so there is one more working day. The 2027 holiday list itself is longer (24 entries against 22 in 2026), but more of those fall on weekends, so they cost fewer working days.
Which months are short
In 2026 February is the shortest at 17 days because the Seollal holiday takes three weekdays. In 2027 both February (18 days) and May (18 days) are the shortest. May 1, 2027 is a Saturday, so May 3 becomes a substitute holiday, and with Children’s Day (May 5) and Buddha’s Birthday (May 13) there are three weekday holidays.
In September the three Chuseok days (14th to 16th) are all weekdays. In October the substitute holidays for National Foundation Day (4th) and Hangeul Day (11th) land on weekdays. If you set monthly deadlines, remember these months have fewer days to work with.
Things to check when you count
- Temporary holidays and election days - 2027 election days and temporary holidays are not in the data yet. Once set, the working days of that month drop. The June 3, 2026 local election day is counted as a holiday.
- Company-specific days off - Founding anniversaries and year-end closures are not in these numbers. Subtract the holidays in your own work rules separately.
- Pay method and coverage - Whether you are paid monthly or daily, and whether holidays count as paid days off, depends on the workplace. Check Article 55 (Holidays) of the Labor Standards Act and your company rules. These counts are calendar days, not a final payroll figure.
- Saturday work - On a Monday-to-Saturday schedule, Saturday is a working day, so this table does not apply directly. The Hyuilmoa workday calculator shows the six-day basis separately.
Public holidays follow the Regulation on Public Holidays of Government Offices, and calendar dates follow the official almanac notice (wolryeok yoham). See the full-year tables and any date range in the workday calculator, and find good days to attach leave in the leave planner.