Business Days Calculator

The business days calculator counts the number of working days between two dates, excluding weekends and public holidays for your chosen country or region. It is used by contract managers, HR teams, accountants, and project planners who need to measure durations in business days rather than calendar days.

How to Use the Business Days Calculator

1. Enter a start date and an end date.
2. Select your country or region to apply the correct public holiday schedule.
3. Choose whether to include or exclude the start and end dates from the count.
4. Click Calculate.
5. Read the number of business days in the results panel.

The Formula

The business days count is calculated by stepping through each calendar day in the range and counting only those that fall on a weekday (Monday to Friday) and are not listed as public holidays.

Business days = Count of days where: day of week is Monday-Friday AND date is not a public holiday

Alternatively, a faster formula calculates the number of weeks and partial weeks in the range and subtracts the number of weekend days and public holidays:

1. Total calendar days = End date - Start date
2. Subtract weekend days: count the number of Saturdays and Sundays in the range
3. Subtract public holidays that fall on weekdays within the range
4. Result = Business days

Real-World Example

You need to count the business days in the month of January 2026 in England.

• January 2026 has 31 calendar days.
• Saturdays and Sundays in January 2026: approximately 8 weekend days (4 Saturdays, 4 Sundays).
• New Year's Day (1 January) falls on a Thursday in 2026, a bank holiday.
• 31 - 8 - 1 = 22 business days in January 2026 in England.

Note that Scotland observes 2 January as an additional bank holiday, giving Scotland only 21 business days in January 2026.

Business Days vs Calendar Days in Contracts

Many commercial and legal agreements specify timelines in business days. A "net 30" payment term typically means 30 calendar days, while "30 business days" means approximately six calendar weeks. Delivery contracts, legal notices, regulatory filings, and employment notice periods may each use different conventions. Reading contracts carefully to determine whether days means calendar days or business days is essential to avoid missed deadlines. When in doubt, request clarification in writing.

Frequently Asked Questions

Are public holidays the same across the UK? No. England and Wales, Scotland, and Northern Ireland each have their own bank holiday calendars. Scotland observes St Andrew's Day (30 November) and has different New Year's arrangements. Northern Ireland observes St Patrick's Day (17 March) and the Battle of the Boyne (12 July). If your work spans multiple UK regions, ensure you apply the correct regional calendar.

What if a bank holiday falls on a weekend? In the UK, when a bank holiday falls on a Saturday or Sunday, a "substitute" bank holiday is given on the next available weekday, typically the following Monday. The business days calculator accounts for substitute holidays automatically when using an up-to-date holiday list.

Does the calculator handle international business days? Yes, if you select the appropriate country. Public holiday schedules differ significantly between countries. A business day in the UK is not necessarily a business day in the US, France, or Australia. For international projects, you may need to calculate business days separately for each country and identify which days are working days in all relevant locations.

Why does the business day count sometimes differ from my company's count? Some companies observe additional holidays beyond statutory bank holidays (such as a company-specific "founder's day" or Christmas shutdown period). If your employer has a custom holiday calendar, you may need to adjust the result manually to subtract those extra days.

Also try these free tools:

• Workday Calculator
• Day Counter
• Date Calculator

Business days month by month in 2026

The month of January above is the worked example. The whole year, counted the same way from the published bank holiday dates for England and Wales, looks like this:

Over a year the pattern is stable: a month runs between 28 and 31 calendar days, of which 8 to 10 are weekend days, so the answer lands between 19 and 23 before holidays are applied. May 2026 is the shortest working month at 19 business days, with two bank holidays and ten weekend days. July is the longest at 23.

On the four quarterly views

Contract deadlines and reporting periods are often set per quarter or per half, and the counts above are the reason a "60 business day" project boundary is not the same as three months. 60 business days at roughly 21 per month is closer to thirteen weeks.

Why the 31 day month has 9 weekend days

A count that treats every month as four Saturdays and four Sundays loses a day whenever the month is 31 days long, because four weeks is 28 days and the remaining days have to fall somewhere. January 2026 starts on a Thursday, which gives 5 Thursdays and 5 Fridays against 5 Saturdays and 4 Sundays. The worked example further up counts from an estimate of eight weekend days and returns 22. Counting the calendar gives nine weekend days, five of them Saturdays, so the calendar count is 21 for England and Wales once New Year's Day is removed, and 20 for Scotland once 2 January is added. The weekday count is 22, and after removing New Year's Day on Thursday 1 January the business day total is 21 for England and Wales and 20 for Scotland, which also observes 2 January.

The general rule is worth keeping: check whether the month starts on a Friday or a Saturday, because those two cases give five Saturdays, and any estimate built on a fixed four-week month will overshoot. The table above does the counting from the calendar rather than from an average.

Worked example: 30 business days from a Monday

Start on Monday 5 January 2026 and count 30 business days, excluding weekends and the bank holidays in the table.

The count runs through January: 5 to 9 January is 5 business days, then 12 to 16, 19 to 23 and 26 to 30 January each give 5 more, for 20 by the end of the month. February 2 to 6 adds 5, bringing the total to 25, and February 9 to 13 adds the last 5. The thirtieth business day is Friday 13 February 2026.

The gap between the two rows is nine calendar days on identical starting dates, which is the practical reason a clause that says "30 days" and a clause that says "30 business days" cannot be treated as interchangeable.

Inclusive and exclusive counting

The start date and the end date can each be counted or left out, which gives four possible answers for one range. Taking Monday 5 January to Friday 9 January 2026:

Notices drafted as "within 5 business days of the date of this notice" or "5 business days from the date of this notice" do different things, because the first excludes the notice date and the second may include it. The calculator's include and exclude options exist for this reason, and the convention used by the other side is worth putting in writing before a deadline depends on it.

Where the holiday dates come from

The holiday dates behind every figure on this page come from GOV.UK's published bank holiday calendar for England and Wales, which marks substitute days explicitly. Boxing Day 2026 is the clearest case: 26 December falls on a Saturday, so the substitute day moves to Monday 28 December, and December 2026 still returns 21 business days because Christmas Day and the substitute day take two weekdays out of a month with eight weekend days.