Working days, also called business days, are the days that count for deadlines, deliveries, and notice periods, and they exclude weekends and public holidays. To calculate them, you take the total number of days in a period and subtract the weekends and any holidays that fall on a weekday. It sounds simple, and by hand it mostly is, but two things trip people up: which days count as the weekend where you are, and whether to include the start date. This guide covers the by-hand method, the spreadsheet function that does it instantly, and how weekend conventions differ around the world. To count the raw days between two dates first, the CalcRange Date Difference Calculator handles that part.
What Counts as a Working Day
A working day is any day a business is normally open, which in most of the world means Monday to Friday, excluding public holidays.
The reason working days matter is that a lot of official timing is measured in them rather than calendar days. A “5 working day” delivery, a “30 business days” refund window, or a contractual notice period all skip weekends and holidays, so the calendar date they land on is later than a plain day count would suggest. Five working days from a Thursday is not the following Tuesday; it is the Thursday after, because a weekend sits in between. Getting this right matters most for deadlines with consequences, like filing dates, payment terms, and service-level agreements, where being a day out can be costly.
The By-Hand Method
Counting working days by hand comes down to three steps.
- Count the total number of days in the period, deciding first whether the start date itself counts.
- Subtract the weekend days. A quick way is to work out how many complete weeks the period spans and multiply by two, then check the leftover days for any Saturdays or Sundays.
- Subtract any public holidays that fall on a weekday, since holidays landing on a weekend are already excluded.
What is left is the number of working days. For short spans you can simply list the dates and cross off weekends and holidays, which is quick and hard to get wrong. For longer ones, the weeks-times-two shortcut saves time: a 30-day period spans roughly four full weeks, so about eight weekend days come out before you even look at holidays.
A Worked Example
Take the period from Monday 1 June 2026 to Friday 12 June 2026, counting both ends, and assume no public holidays in that window.
That is 12 calendar days in total. Within it there is one full weekend, Saturday 6 and Sunday 7 June, which is two weekend days. So the working days are 12 − 2 = 10. You can check it by listing: the 1st to the 5th is five working days, the 6th and 7th are the weekend, and the 8th to the 12th is another five, giving ten. If a public holiday fell on, say, Monday 8 June, you would subtract one more and get nine working days. This is exactly the kind of count that decides when a “10 working day” process actually finishes.
Doing It in a Spreadsheet
For anything beyond a short span, a spreadsheet does this in one function and handles holidays for you.
In Excel and Google Sheets, =NETWORKDAYS(start_date, end_date, [holidays]) returns the number of working days between two dates, counting both ends and excluding Saturdays and Sundays. Feed it a range of holiday dates as the optional third argument and it subtracts those too, if they fall on weekdays. So =NETWORKDAYS(A2, B2, C2:C10) counts business days between the dates in A2 and B2, skipping the holidays listed in C2 to C10. If your weekend is not Saturday and Sunday, use NETWORKDAYS.INTL, which takes a weekend code, for example code 7 for a Friday and Saturday weekend. The companion function WORKDAY goes the other way, adding a number of working days to a start date to find the finish date, which is how you answer “what date is 10 working days from now.”
Count the Days First
If you need the plain number of days between two dates before adjusting for weekends, the CalcRange Date Difference Calculator gives you that total. Our guide on how to calculate days between two dates covers the inclusive-versus-exclusive counting question that also applies to working days.
Weekends Are Not the Same Everywhere
The Monday-to-Friday assumption is a Western default, and it is wrong in a good part of the world.
In many countries the working week and weekend sit on different days. A number of Middle Eastern countries have used a Friday and Saturday weekend, with the working week running Sunday to Thursday, though several have shifted their arrangements in recent years. Some places take only Friday, or only Sunday, as the rest day. This matters whenever you calculate working days across borders: a “5 working day” delivery from a supplier whose weekend is Friday and Saturday finishes on different calendar dates than one whose weekend is Saturday and Sunday. Always base the count on the weekend and public holidays of the place whose deadline you are working to, and set the weekend code accordingly if you use a spreadsheet. Public-holiday calendars differ by country too, and often by region within a country.
Common Mistakes
- Assuming a Saturday-Sunday weekend everywhere. Check the local working week, especially for cross-border deadlines.
- Forgetting public holidays, which turns a correct weekend count into a deadline that is a day or two early.
- Getting the inclusive-exclusive choice wrong, so the count is off by one at the start or end.
- Subtracting holidays that fall on a weekend, which were never working days to begin with; only weekday holidays reduce the count.
- Using NETWORKDAYS with the default weekend when your region’s weekend is different; use NETWORKDAYS.INTL with the right code instead.
Frequently Asked Questions
How do I calculate working days between two dates?
Count the total days in the period, subtract the weekend days, then subtract any public holidays that fall on a weekday. By hand, listing short spans and crossing off weekends is reliable; for longer ones, multiply the number of full weeks by two for the weekend days. In a spreadsheet, the NETWORKDAYS function does it in one step, including a holiday list.
What is the difference between working days and calendar days?
Calendar days count every day, including weekends and holidays. Working days count only the days a business is normally open, usually Monday to Friday excluding public holidays. Because working days skip weekends and holidays, a deadline measured in working days lands on a later calendar date than the same number of calendar days would.
Which spreadsheet function counts business days?
Use NETWORKDAYS(start, end, holidays) in Excel or Google Sheets to count working days between two dates, excluding Saturdays, Sundays, and any holidays you supply. For a non-standard weekend, use NETWORKDAYS.INTL with a weekend code. To find the date a number of working days ahead, use WORKDAY, which adds business days to a start date.
Do working days include the start date?
It depends on the convention, which is why you should decide first. NETWORKDAYS counts both the start and end dates. Some contracts count from the day after an event, so “5 working days from receipt” may start the next working day. Check the specific rule; the inclusive-or-exclusive choice is the most common source of off-by-one errors.
Are weekends always Saturday and Sunday?
No. Many countries, particularly in the Middle East, have used a Friday and Saturday weekend with a Sunday-to-Thursday working week, and some take only one rest day. Several have adjusted their arrangements recently. When calculating working days, use the weekend of the place whose deadline applies, and set the spreadsheet weekend code to match.
How do public holidays affect the count?
A public holiday that falls on a weekday reduces the working-day count by one, because that day is not a business day. A holiday that lands on a weekend does not change the count, since weekends are already excluded. In spreadsheets, supply the holiday dates to NETWORKDAYS and it subtracts only the weekday ones automatically.
How do I find the date that is 10 working days away?
Add working days to your start date, skipping weekends and holidays, until you have counted ten. In Excel or Google Sheets, WORKDAY(start_date, 10, holidays) returns the date exactly ten working days after the start, accounting for the weekend and any holidays you list. By hand, step forward day by day and count only weekdays that are not holidays.
The Bottom Line
Working days are total days minus weekends and weekday public holidays, and that single subtraction answers most business-day questions. By hand, list short spans or use the weeks-times-two shortcut for longer ones; in a spreadsheet, NETWORKDAYS does it instantly and WORKDAY finds a future deadline. The one thing to confirm every time is the local weekend and holiday calendar, since neither is the same worldwide. To get the raw day count first, the date difference calculator is the place to start.
Last reviewed: August 2026. Recommended editorial review: every 12 months. Weekend conventions and public holidays vary by country and change over time; verify against the relevant local calendar.