How to add business days to a date
To add business days, move one calendar date at a time and only count dates that match your business calendar.
Method
- Start with the original date.
- Move to the next calendar day.
- If the date is Saturday, Sunday, or an excluded holiday, skip it.
- If it is a counted business day, subtract one from the remaining count.
- Repeat until the remaining count reaches zero.
The original start date is usually not counted as the first added business day. This keeps "add 1 business day" aligned with the next qualifying workday.
Forward and backward counts
The same rule works in either direction. To subtract business days, move backward one calendar date at a time and count only dates that qualify under the calendar. This is useful for finding prep deadlines before a target date, such as sending a reminder five business days before an invoice due date.
Holiday calendars matter
The result can change when a holiday falls inside the count. For example, adding ten business days around a federal holiday will usually land one calendar day later than a weekday-only count. If your organization observes extra holidays or local closures, use that schedule instead of a general federal calendar.
Spreadsheet tip
When you reproduce this in a spreadsheet, keep holidays in a separate source table instead of typing them into formulas. That makes the calculation easier to audit and reduces the risk of silently missing an observed holiday.