How do I count business days?

Subtract weekends and public holidays from the total number of days.

How many business days in a week?

Five, Monday to Friday, unless a public holiday falls in it.

Is a business day the same as a working day?

Yes; both mean a weekday that isn't a public holiday.

How to Count Business Days

Published 8/6/2025 · 3 min read · Everyday calculators

Lena Hoffmann — Science & education writer at Allin

Mathematics · Physics

Checked against 2 sources

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In short

Business days are weekdays — Monday to Friday — excluding weekends and public holidays. To count them between two dates, take the total days, subtract the weekends, then subtract any holidays that fall on a weekday. From Monday to the next Monday is 7 days but only 5 business days. Delivery and payment terms are usually quoted in business days, not calendar days.

Business days are weekdays minus holidays. Here's what counts, how to work them out between two dates, why holidays complicate it, and where it matters.

What a business day is

A business day is a day when normal business is done — in most of the world, Monday to Friday, leaving out Saturdays, Sundays and public holidays. It matches the standard working week, which is why it's the natural unit for anything commercial. The exact days can vary: some regions treat Saturday differently, and each country's holidays differ, but the core idea is the same everywhere — a weekday the offices and banks are open.

Counting them by hand

To count business days between two dates, start with the total number of days and take out the non-working ones. First subtract the weekends: every full week contains two, so a stretch of 7 days loses 2, leaving 5. Then subtract any public holidays that land on a weekday (a holiday on a Sunday doesn't reduce the count further, since Sunday was already out). Finally, be clear whether your span includes the start date or not — it shifts the answer by one.

Why holidays complicate it

Weekends are predictable, but public holidays are where hand-counting gets messy. They vary by country, and often by region within a country, so the same two dates can enclose a different number of business days depending on where you are. Some holidays move each year, like those tied to Easter, and some shift to the nearest weekday when they fall on a weekend. This is exactly why a business-day tool with a built-in holiday calendar for your country is worth using for anything important.

Where it matters

Business days are the currency of deadlines. Shipping estimates, payment terms like 'net 30 days', bank transfer clearing times, notice periods and service-level agreements are almost always counted in working days, not calendar days. That's why '5 business days' can be a week and a half on the calendar once a weekend and a holiday are in the way. Whenever a commitment is quoted to you, check which kind of day it means before you plan around it.

Worked with our own calculator

Business days calculator

Given

Start date: 1985-03-20
End date: 1985-03-20

Result

Business days: 1
Total days: 1

These figures are produced by the calculator below, not typed in by hand — they are recomputed whenever the tool changes.

Run it on your own figures →

Frequently asked questions

How do I count business days?: Subtract weekends and public holidays from the total number of days.
How many business days in a week?: Five, Monday to Friday, unless a public holiday falls in it.
Is a business day the same as a working day?: Yes; both mean a weekday that isn't a public holiday.

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Sources

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