Tool guide
Add Business Days to a Date Calculator
Find a future or past date by adding or subtracting business days while skipping weekends and selected holidays. Use this guide before launching the calculator to avoid off-by-one surprises.
Published: December 28, 2025 · Updated: December 28, 2025 · By FinToolSuite Editorial
Disclaimer
- Educational purposes only; not legal or financial advice.
- Examples are illustrative and simplified.
- Results depend on your inputs and assumptions and are not guaranteed.
- See the Privacy Policy; do not share personal data.
Quick answer
- Business days exclude weekends and selected holidays.
- Holiday presets and custom holidays can shift the result.
- Cutoff rules can move the effective start date.
Quick example: Start on Friday, add 3 business days with Saturday–Sunday weekends and holidays excluded. You land on Wednesday unless a holiday interrupts.
What this calculator does
- Add or subtract business days from any start date.
- Select weekend patterns or define custom weekend days.
- Load holiday presets by country and year.
- Add custom holidays for company or regional events.
- Toggle holiday exclusion on or off.
- Enable cutoff time rules based on start time.
- Choose whether to count the start date.
- Adjust results forward or backward if they land on non-working days.
- Pick output format: local date or ISO.
When to use it
- Invoice due dates and payment terms.
- Shipping or delivery ETAs.
- Service-level agreement clocks.
- Payroll cutoff planning.
- HR onboarding timelines.
- Project milestone scheduling.
- Legal notice periods.
- Procurement lead times.
- Contract renewal reminders.
- Maintenance windows that avoid weekends.
- Vendor response targets.
- Compliance or filing deadlines.
Inputs explained
Start date and start time (optional)
Choose the anchor date and, if needed, a start time for cutoff logic. Times after the cutoff can shift the effective start.
Add vs subtract direction
Pick add to move forward or subtract to move backward.
Number of business days
Enter how many working days to count.
Weekend pattern and custom weekends
Use presets like Saturday–Sunday or Friday–Saturday, or choose custom weekdays to exclude.
Holiday preset and holiday year
Load a static holiday list by country and year. It is illustrative; add your own dates for accuracy.
Exclude holidays toggle and custom holidays
Turn holiday exclusion on or off and add custom holiday dates to reflect regional or company closures.
Cutoff and start rules
Enable cutoff, set the cutoff time, and decide if subtract mode also honors cutoff. After-cutoff times can move the effective start.
Advanced options
Choose whether to count the start date, select how to adjust if the result is non-working, and pick the output format (local or ISO).
How it works
- Normalize the start date and apply cutoff if enabled.
- Walk day by day in the chosen direction.
- Skip weekend days based on your pattern.
- Skip preset and custom holidays when holiday exclusion is on.
- Count only working days until the target is reached.
- Adjust the final date if it lands on a non-working day according to your setting.
- Report calendar span, skipped weekends, and skipped holidays.
Worked examples
Example A: Start date is on a weekend
Inputs used: start Saturday, add 4 business days, weekend Sat–Sun, holidays excluded. The calculator skips Saturday and Sunday, counts Monday as day one, and lands on Thursday.
Result: Thursday of the same week.
Example B: Cutoff time and holiday
Inputs used: start Wednesday 18:30, cutoff 17:00 enabled, add 5 business days, weekend Sat–Sun, holiday on the following Monday. Start shifts to Thursday, the holiday is skipped, and the result lands the next Thursday.
Result: Thursday of the next week after the holiday.
Common mistakes
- Counting the start date unintentionally and creating off-by-one errors.
- Leaving the start date on a weekend and expecting counting to begin immediately.
- Using the wrong holiday year with the selected preset.
- Forgetting custom weekend patterns for non-standard schedules.
- Assuming the preset holiday list is complete for your region.
- Ignoring the cutoff rule when entering a late start time.
- Not choosing how to adjust results that land on non-working days.
- Leaving holiday exclusion on when testing weekend-only scenarios.
FAQ
What is a business day?
A working day that is not in your weekend pattern and not on the selected holiday list.
Do you count the start date?
You can choose to count it or start from the next eligible business day.
What if the start date is a weekend or holiday?
The calculator skips it and moves to the next or previous business day based on your settings.
How are holidays handled?
Load preset holidays by country and year, toggle them off, and add custom dates.
Can I subtract business days?
Yes. Switch to subtract to move backward while skipping non-working days.
What does cutoff time do?
If enabled, times after the cutoff push the effective start date.
What if the result lands on a non business day?
Choose to move the result forward or backward to the nearest business day.
Are the holiday lists accurate?
They are static and illustrative; add your own dates and confirm critical timelines.
Disclaimer
- Educational purposes only; not legal or financial advice.
- Examples are illustrative and simplified.
- Results depend on your inputs and assumptions and are not guaranteed.
Use the Business Day Calculator
Enter your start date, set weekend and holiday rules, and get a business-day result with skipped counts.