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Add Business Days to a Date

Add N business days to a starting date, skipping weekends and holidays.

Written and maintained by Paul Clark, Redmoon Software · Rules last verified

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Monday, September 21, 2026
Start date: Sep 7, 2026 · Add 10 business days
Due date
2026-09-21
Business days
10

These calculators are for informational purposes only and do not constitute legal, financial, or professional advice.

How the Add Business Days to a Date works

The Add Business Days to a Date calculator moves a start date forward (or backward) by a number of working days, automatically stepping over weekends and the public holidays you select. It answers questions like "what date is 10 business days from today?" without you counting on a calendar.

Because each weekend and holiday inside the span pushes the result further out, adding business days by hand drifts quickly. Letting the tool walk the calendar guarantees the landing date reflects the real working days, not raw calendar days.

Worked example

Add 5 business days to a Thursday and you land on the following Thursday, not Tuesday — the intervening weekend does not count. Drop a public holiday into that window and the result slides one more day to Friday.

Frequently asked questions

Can I subtract business days as well as add them?

Yes. Tick the "Subtract instead of add" checkbox and the same number of business days is counted backwards from your start date — useful for working out the latest date you can begin and still hit a deadline. Leave the day count positive; the checkbox is what reverses the direction.

Does the start date count as day one?

No. Counting begins on the next working day after your start date, which is the standard convention for "N business days from" a date.

How are holidays handled?

Select a country and its public holidays are skipped alongside weekends. You can also add custom closures for company-specific days off.

What this calculator does not do

A limitation you know about costs far less than one you find after the deadline. These are the specific things this tool cannot work out for you.

  • It counts working days forward or backward. It does not know whether the rule you are applying counts business days at all — many statutory periods are calendar days, and the two diverge quickly across a long weekend.
  • Half-days and partial closures are not modelled; a day is either a working day or it is not.

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