How to count business days

By Vijay Jadhav

Business days, or working days, are the days most offices are open: Monday to Friday. Counting them sounds simple, but deadlines are often missed because of a small difference in how the count is done.

The basic count

1. List the days between the two dates.
2. Remove Saturdays and Sundays.
3. Decide whether the start date and the end date count. On this site, the start date (today) is not counted.

A quick shortcut: every full week contains five business days. So 4 weeks and 2 days usually means 20 business days plus however many of the 2 extra days are weekdays.

Public holidays

Public holidays differ by country, and often by state, so this site does not remove them. If a holiday falls in your range, subtract one business day for each.

Common mistakes

• Counting the start day as day one when the contract says "within 10 business days of" it.
• Forgetting that a deadline landing on a Saturday usually moves to the next Monday.
• Using calendar days when the rule says business days, or the other way round.

In spreadsheets

=NETWORKDAYS(start, end) counts weekdays including both dates, and =WORKDAY(start, n) finds the date that is n business days after the start.

See what date is 30 days from today, including the business-day answer.