How to calculate business days (with and without holidays)

"Allow 5–7 business days for delivery." "Your refund will be processed within 10 working days." "Please reply within 3 business days." Business days run through shipping, banking, HR and customer service, yet they are surprisingly easy to miscount. This guide shows exactly how they work.

What is a business day?

A business day (also called a working day) is normally Monday through Friday, excluding public holidays. Saturdays and Sundays never count. Whether a particular holiday counts depends on who is doing the counting: a US bank follows the Federal Reserve holiday calendar, a UK company follows bank holidays, and a business in Pakistan or the UAE follows its own national and religious holidays. Some countries also have a different weekend; in several Middle Eastern countries, for example, the weekend falls on Friday and Saturday.

The fast way to count business days

Every full week contains exactly 5 business days, so you only need to count the leftover days by hand:

1. Count the calendar days in the period.
2. Divide by 7. The whole number is the count of full weeks; multiply it by 5.
3. Walk through the remaining 0–6 days and add 1 for each that is a weekday.
4. Subtract any public holidays that fall on weekdays inside the period.

Example: How many business days from Thursday, October 1 to Friday, December 25, 2026? That is 85 calendar days, which is 12 full weeks (60 business days) plus 1 extra day, a Friday, so 61 business days. Three US federal holidays fall on weekdays inside that period: Columbus Day (Monday, October 12), Veterans Day (Wednesday, November 11) and Thanksgiving (Thursday, November 26), so a federal office would count 58. Christmas Day itself is also a holiday, so if the end date shouldn't count either, the answer is 57.

Adding business days to a date

To find the date that is N business days from today, step forward one day at a time and only count weekdays. A shortcut: every 5 business days moves you exactly one calendar week forward, to the same weekday. Then add the remainder:

If a holiday falls inside the period, push the result forward one business day for each one.

Does the first day count?

Usually not. If a company receives your request on a Monday and promises an answer "within 3 business days", day 1 is Tuesday and the deadline is Thursday. However, some spreadsheet functions, such as NETWORKDAYS, count both the start and end date if they are weekdays. Always check which convention is being used.

Cut-off times

Many businesses treat requests that arrive after a cut-off time, for example 5 p.m. or 2 p.m. for same-day shipping, as received the next business day. An order placed late on Friday is often processed on Monday, which can make a "3 business day" delivery arrive on Thursday.

Business days in Excel and Google Sheets

• =NETWORKDAYS(start, end) counts weekdays between two dates, including both ends.
• =NETWORKDAYS(start, end, holidays) also skips a list of holiday dates you provide.
• =WORKDAY(start, 10) returns the date 10 business days after the start date.
• =NETWORKDAYS.INTL and =WORKDAY.INTL let you choose a different weekend, such as Friday–Saturday.

Business days vs calendar days

Ten business days is about two weeks of calendar time, 20 business days is about four weeks, and a typical year has about 260 or 261 weekdays before holidays. If a promise says "14 days" without the word "business", assume calendar days.

Summary

• Business days are Monday to Friday, minus public holidays that apply to the business.
• Each full week adds 5 business days; count the leftover days by hand.
• The start day usually doesn't count; spreadsheet functions sometimes do count it.
• Holidays and cut-off times push deadlines later, so allow a buffer for anything important.