How to Calculate Business Days Between Two Dates

 

To calculate business days between two dates, decide which weekdays count as working days, whether the start and end dates are included, and which holidays or closures must be excluded. Without those choices, two correct calculations can give different answers for the same dates.

This guide uses a Monday-to-Friday schedule for its examples. That is an illustrative convention, not a calendar that applies to every employer, service, or country. A business-day calculator should make these assumptions visible rather than silently treating every weekday as a working day.

Use the Business Days Calculator to count workdays with your chosen excluded weekdays, closure dates, and boundary settings.

1. Define your working week

Start with the days that are normally eligible. For a Monday-to-Friday schedule, Saturday and Sunday are excluded. A business operating on Saturday or using another weekly closure pattern needs a different calendar. Personal leave, company shutdowns, and public holidays are additional exclusions, not changes to the meaning of a calendar day.

Write down the schedule before counting. If several people or organizations are involved, confirm which calendar governs the task instead of combining different schedules without explanation.

2. Choose whether to count the boundary dates

Including the start date means it can count as a business day if it meets the calendar rules. Excluding it means counting begins after that date. The same distinction applies to the end date. An eligible boundary is not automatically counted unless your convention includes it.

For a Monday-to-Friday schedule with no closures, Monday, November 2, 2026, through Friday, November 6, 2026, contains five business days when both dates are included. Excluding Monday but including Friday gives four. Including Monday but excluding Friday also gives four. Excluding both dates gives three.

3. Remove holidays and closures once

After identifying the eligible weekdays, remove any listed closure that falls inside the selected boundaries. If Wednesday in the five-day example is a closure, the inclusive count drops from five to four.

Do not subtract a Saturday holiday again when Saturdays are already excluded. Likewise, a duplicate entry for the same closure should not remove two days. Keep a dated list of exclusions and check whether the calendar uses the holiday's actual date or a separately observed closure date.

4. Check a range that crosses a weekend

Friday, November 6, through Tuesday, November 10, 2026, spans five calendar dates when both endpoints are included. Under the Monday-to-Friday example, the business days are Friday, Monday, and Tuesday: three in total.

If counting starts after Friday and includes Tuesday, the answer is two business days. This is why subtracting the two date numbers or reading an elapsed calendar duration does not directly answer a business-day question. The selected weekend and boundary rules change the count.

Counting days is different from adding business days

A between-dates calculation starts with two dates and counts eligible days. An add-business-days calculation starts with one date and advances through the calendar until a target count is reached.

Starting after Friday, November 6, 2026, and adding three Monday-to-Friday business days gives Wednesday, November 11, if no closures are excluded. If November 11 is explicitly excluded in the calendar being used, the third eligible day becomes Thursday, November 12. This example shows how the chosen calendar changes the result; it does not establish an organization's holiday policy.

Use Excel with the same assumptions

Excel's NETWORKDAYS function counts eligible days between two dates using a Saturday-Sunday weekend and an optional holiday list. NETWORKDAYS.INTL supports configurable weekends. Their boundary behavior must match the question you are answering, so do not assume an inclusive spreadsheet count matches a process that begins after the start date.

Use real spreadsheet dates rather than ambiguous date text, and keep closure dates in a separate range. Check the function help for your spreadsheet application and version, especially when changing weekend settings or reusing a formula from another workbook.

Verify the calendar before relying on a deadline

Compare a short sample range with a manual count before using a long result. Confirm the date order, working week, included boundaries, and exclusions. For a same-day range, an included eligible date can count as one day; an excluded or closed date does not.

Shipping promises, court rules, tax deadlines, and employment agreements may define business days differently or include cutoff times. This general counting method does not determine those rules. Confirm the relevant calendar and instructions with the organization responsible for the deadline.

Need calendar days instead?

For elapsed days, inclusive date counts, or adding and subtracting calendar days, see how to calculate days between dates. Unlike a business-day count, that method includes weekends and holidays.