How to Count Working Days Between Two Dates — Formula, Examples, and Edge Cases

Learn how to calculate business days between dates, handle holidays and custom weekends, and avoid common mistakes in project planning and payroll.

The Quick Answer

To count working days between two dates, count every day in the range that is not a weekend and not a holiday.

Working days = Total days − Weekend days − Holidays (that fall on weekdays)

For a standard Monday–Friday work week with no holidays:

Working days ≈ Total weeks × 5 + remaining weekdays

For anything involving holidays, custom weekends, or multi-month spans, use a working days calculator to avoid manual errors.

What Counts as a "Working Day"?

A working day (also called a business day or weekday) is any day that is part of the standard work week in a given country and is not a public holiday. In most of the world, that means Monday through Friday. But this varies:

Region Standard Work Days Weekend Days
Most countries (US, EU, UK, etc.) Monday – Friday Saturday & Sunday
UAE, Saudi Arabia (post-2022) Monday – Friday Saturday & Sunday
Some Middle Eastern countries Sunday – Thursday Friday & Saturday
Israel Sunday – Thursday (partial Friday) Friday afternoon & Saturday
Brunei Monday – Thursday, Saturday Friday & Sunday

The point: "working day" is not universal. If you're calculating across regions, confirm which days are working days in each relevant country.

Skip the Manual Count

Working Days Calculator

Enter two dates, choose your weekend days, and add holidays. Get an instant breakdown of working days, weekends, and holidays.

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The Formula (Step by Step)

Step 1: Count Total Calendar Days

Subtract the start date from the end date, then add 1 (to include both endpoints).

Total days = (End date − Start date) + 1

Example: January 6 to January 17, 2025 → 17 − 6 + 1 = 12 calendar days.

Step 2: Count Complete Weeks

Divide total days by 7 to find full weeks:

Full weeks = floor(Total days ÷ 7)

12 ÷ 7 = 1 full week with 5 remaining days.

Step 3: Count Weekend Days

Each full week contains 2 weekend days (for a Sat–Sun weekend). For the remaining days, check each one individually.

Weekend days from full weeks = Full weeks × 2

For the remaining 5 days (starting from the day after the last full week), check: are any of them Saturday or Sunday?

Step 4: Subtract Holidays on Weekdays

Only subtract holidays that fall on a working day. A holiday on a Saturday doesn't reduce your working day count (it's already excluded).

Working days = Total days − Weekend days − Weekday holidays

Worked Example

Dates: January 6 (Monday) to January 17 (Friday), 2025. US Federal holidays apply.

  1. Total calendar days: 12
  2. Full weeks: 1 (7 days). Remaining: 5 days.
  3. Weekend days: 1 full week × 2 = 2. Remaining 5 days (Mon Jan 13 – Fri Jan 17) = 0 weekend days. Total weekends: 2.
  4. Holidays: January 20 is MLK Day, but that's outside our range. Weekday holidays: 0.
  5. Working days: 12 − 2 − 0 = 10 working days.

Another Example (With Holidays)

Dates: December 22 (Monday) to January 2 (Friday), 2025–2026. US Federal holidays.

  1. Total calendar days: 12
  2. Weekend days: Sat Dec 27, Sun Dec 28 = 2. (Dec 22 is Mon, Jan 2 is Fri.)
  3. Holidays on weekdays: Dec 25 (Thu) = Christmas. Jan 1 (Thu) = New Year's. 2 holidays.
  4. Working days: 12 − 2 − 2 = 8 working days.

Note: If Christmas or New Year's falls on a weekend, the observed holiday shifts to Monday or Friday. Check your country's rules for observed holidays.

Common Scenarios

Project Deadlines

"The client needs this in 10 business days."

Start from the next working day after the request. Count forward 10 days, skipping weekends and holidays. If the request comes on Friday afternoon, day 1 is Monday.

Many contracts define "business day" explicitly. Check the contract language — some exclude the start day, some include it.

Payroll Periods

Bi-weekly payroll typically covers 10 working days. But months with holidays may have 9 or fewer. This matters for:

  • Hourly employee pay calculations
  • PTO accrual rates
  • Overtime tracking

A standard year has 260 working days (52 weeks × 5). Subtract your country's public holidays for the actual number. In the US, with 11 federal holidays: 249 working days.

Shipping and Delivery

"Delivery in 3–5 business days" means 3–5 working days, not calendar days. A Friday order with 3 business day shipping arrives Wednesday, not Monday.

International shipping adds complexity: the origin country and destination country may have different holidays and weekends.

Legal and Financial Deadlines

Courts, banks, and regulators use "business days" in specific legal definitions. These usually mean Monday–Friday excluding federal or bank holidays. Settlement periods (like T+2 for stock trades) count business days.

Important: Legal definitions of "business day" vary by jurisdiction. When a legal deadline is involved, verify the applicable definition.

Edge Cases to Watch

Holiday Falls on a Weekend

If a holiday falls on Saturday, the observed day off is usually Friday. If it falls on Sunday, the observed day is usually Monday. This is standard in the US but not universal — check local rules.

Overlapping Holidays

Some regions have consecutive holidays (like Christmas + Boxing Day, or Golden Week in Japan). Count each holiday that falls on a weekday separately.

Leap Years

February 29 in a leap year is a normal working day (if it's a weekday). It adds one calendar day to any range that spans it, which may or may not add a working day depending on the day of the week.

Start Date = End Date

If the start and end date are the same day, the result is either 1 (if it's a working day) or 0 (if it's a weekend or holiday).

Ranges Spanning Multiple Years

Holiday lists change year to year. Easter moves. Thanksgiving moves. Floating holidays like MLK Day move. Make sure to use the correct year's holiday dates for each portion of the range.

Working Days per Month (Reference)

Approximate working days per month in a standard Mon–Fri work week (no holidays):

Month Days Typical Working Days
January 31 21–23
February 28–29 20–21
March 31 21–23
April 30 21–22
May 31 21–23
June 30 21–22
July 31 21–23
August 31 21–23
September 30 21–22
October 31 21–23
November 30 21–22
December 31 21–23

The exact number depends on which day the month starts. Subtract public holidays for your country to get the actual count.

Common Mistakes

Forgetting the inclusive count. January 1 to January 3 is 3 days, not 2. Off-by-one errors are the most common mistake in date calculations.

Counting holidays that fall on weekends. If Christmas is on a Saturday, don't subtract it from working days — the Saturday is already excluded.

Using the wrong year's holidays. Easter 2025 and Easter 2026 fall on different dates. Floating holidays shift every year.

Assuming all countries use Mon–Fri. Some countries use Sun–Thu. Others have half-day Fridays or Saturdays. Confirm the local work week.

Ignoring observed holidays. A holiday on Sunday may create an observed Monday off. Whether to count the observed date depends on your employer's or jurisdiction's policy.

Frequently Asked Questions

How many working days are in a year?

A standard year has 52 weeks × 5 working days = 260 working days before subtracting holidays. In the US with 11 federal holidays, that's 249. In Germany with 9–13 public holidays (varies by state), it's roughly 247–251.

Does the NETWORKDAYS formula in Excel work the same way?

Yes. Excel's NETWORKDAYS(start, end, holidays) counts weekdays between two dates and optionally excludes holidays. NETWORKDAYS.INTL lets you define custom weekends. Both include the start and end dates.

How do I count working days backward from a deadline?

Start from the deadline date. Count backward, skipping weekends and holidays. If the deadline is Friday and you need 5 business days, the start date is the previous Monday (assuming no holidays in between).

What's the difference between "business days" and "working days"?

In practice, they're the same: weekdays that aren't public holidays. Some legal contexts define them differently, so check the specific definition if it matters for a contract or regulation.

Do half-days count as working days?

It depends on context. For most business day calculations (shipping, legal deadlines, project timelines), a half-day still counts as one working day. For payroll, it may count as 0.5.

How do I handle time zones for international working day calculations?

Use the time zone of the relevant party. For shipping, use the origin's time zone for dispatch and the destination's for delivery. For contracts, the governing law's jurisdiction usually determines which calendar applies.

How many working days between two dates if I work 6 days a week?

If Saturday is a working day for you, use a calculator that supports custom weekend rules. You'll have approximately 312 working days per year (52 × 6) minus holidays.

Are bank holidays the same as public holidays?

Not always. "Bank holiday" originated in the UK and refers to days when banks close. In practice, most employers also close on bank holidays, but some industries (retail, healthcare, hospitality) may not observe all of them.

How do I calculate working hours between two dates?

Multiply working days by your daily work hours. For a standard 8-hour day: working hours = working days × 8. Adjust for any half-days or different shift lengths.

Can I use this for SLA (Service Level Agreement) calculations?

Yes. SLAs often define response or resolution times in "business hours" or "business days." Count working days between the ticket creation date and the resolution date, then compare against the SLA target.

Try It Yourself

Use the working days calculator to count business days between any two dates. Choose your weekend days (Mon–Fri, Sun–Thu, or custom), add holidays from preset lists or manually, and get an instant breakdown showing working days, weekends, holidays, and a visual calendar.

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