Business Days vs. Holidays: How the Math Works
How business-day counting works, and the difference between a national holiday, a transfer holiday, and a citizens' holiday in Japan's calendar.
What counts as a business day?
A business day is a day when normal operations run: it excludes Saturdays, Sundays, and public holidays. Because calendar days and business days rarely match, calculating a deadline or delivery date means subtracting every weekend day and holiday that falls between the start and end dates, not just the raw day count. Some industries also treat Saturday as a non-working day, which removes one more day from the count.
The difference between a national holiday, a transfer holiday, and a citizens' holiday
A 'national holiday' is a specific date fixed by law. A 'transfer holiday' (furikae kyujitsu) is created when a national holiday falls on a Sunday: the next weekday that is not already a holiday becomes a holiday instead. A 'citizens' holiday' (kokumin no kyujitsu) applies to a weekday sandwiched between two national holidays, even though that day is not itself a holiday or a Sunday. In 2026, Japan has one transfer holiday (May 6) and one citizens' holiday (September 22).
When does a transfer holiday occur?
A transfer holiday is triggered whenever a national holiday lands on a Sunday, and it shifts to the first following weekday that isn't already a holiday. If several holidays fall back to back, the transfer date can shift further out until an open weekday is found. In 2026, Constitution Memorial Day (May 3) falls on a Sunday, but May 4 and May 5 are already holidays, so the transfer holiday lands on May 6.
When does a citizens' holiday occur?
A citizens' holiday applies to a weekday that sits between two national holidays, as long as that day is not already a holiday or a Sunday. In 2026, September 22 sits between Respect for the Aged Day (September 21) and the Autumnal Equinox (September 23), so it becomes a citizens' holiday. Without this rule, that day would have stayed a normal working day.
Pitfalls in business-day calculations
Common mistakes include assuming a transfer holiday applies when a holiday falls on a Saturday (it only applies on Sundays), forgetting that the holiday calendar changes from year to year, and confusing a company's internal closures, like a founding anniversary, with the legally defined public holidays. Checking the current year's official holiday list before calculating is the safest habit.
Frequently asked questions
When is a transfer holiday created?
When a national holiday falls on a Sunday. The next weekday that isn't already a holiday becomes the transfer holiday.
What is a citizens' holiday?
A weekday sandwiched between two national holidays, where that day itself isn't a holiday or a Sunday. September 22, 2026 is one example.
Does a holiday falling on Saturday create a transfer holiday?
No. The transfer-holiday rule only applies when a national holiday falls on a Sunday.