How Long Is 11 Business Days? Weekends, Holidays and Examples

How long is 11 business days in calendar days?#

Five business days make one working week, so 11 business days is two working weeks (10 days) plus one more day. Two working weeks always cover 14 calendar days, and the extra day adds one more calendar day, unless that extra day lands after a weekend.

Notice the last three rows. If an order is placed on a Friday, Saturday or Sunday, the first business day counted is the following Monday, so all three reach the same end date: Monday 26 October.

Business days vs calendar days#

Calendar days are every day on the calendar, weekends and holidays included. Business days, also called working days or workdays, are the days an organisation is normally open: usually Monday to Friday, minus public holidays. A promise of “10 calendar days” and “10 business days” can be almost a week apart.

The 5, 10 and 15 rows are the same from every weekday, because a whole number of working weeks always spans whole calendar weeks. Counts that are not a multiple of five, such as 11, depend on the day you start.

The difference matters when you set terms yourself. If you write payment terms on an invoice, for example with the invoice generator, say whether “14 days” means business days or calendar days.

Does the start day count as a business day?#

There are two different questions here, and the convention differs for each.

• Adding business days to a date (“11 business days from Monday”): the start day is day zero. Counting begins on the next working day, so 1 business day from Monday is Tuesday. This is how most delivery and response times are read.
• Counting business days between two dates (“how many working days from the 5th to the 20th?”): the start date counts if it is a working day, and the end date counts only if you choose to include it.

Business days from today: a 1 to 15 day table#

Find the number of business days in the left column and the day you start along the top. Each cell shows the weekday you land on and, in brackets, how many calendar days later that is.

The table is built for a normal week. If a public holiday falls inside your range, move one working day later for each holiday.

How to calculate business days between two dates#

1. Count the calendar days in the range, deciding first whether the end date is included.
2. Subtract the weekend days inside that range.
3. Subtract each public holiday that falls on a working day. A holiday on a Saturday or Sunday is already excluded, so do not subtract it twice.

For longer ranges, a shortcut helps: each full week contributes exactly five business days, so only the leftover days at the end need counting by hand. The date difference calculator gives the total calendar days if you want to check that part separately.

When the weekend isn’t Saturday and Sunday#

Not every workplace rests on Saturday and Sunday. In several countries the working week runs Sunday to Thursday, and some businesses work six days a week. The business days calculator lets you tick any combination of days as the weekend.

With a Friday–Saturday weekend the result from a Monday happens to match the usual one, but the days in between differ: Friday is skipped and Sunday is worked. Starting from Sunday 4 October, 11 business days with a Friday–Saturday weekend ends on Monday 19 October.

How public holidays change the count#

Public holidays are set by country, and often by region. England and Wales, Scotland and Northern Ireland each have their own list of bank holidays, and the dates move from year to year. Always add the holidays that apply to the business doing the work, not to you as the customer.

Adding Saturday 26 December to the holiday list as well changes nothing: it is already a weekend day, and the calculator never removes a day twice.

Counting business days backwards from a deadline#

Sometimes you know the deadline and need the start date, for example the last day to post a notice that must arrive 11 business days before a meeting. Enter a negative number in the calculator to count backwards: 11 business days before Tuesday 20 October 2026 is Monday 5 October 2026.

How to use the business days calculator#

1. Choose Add business days to find an end date, or Between two dates to count working days in a range.
2. Enter the start date (it fills in today’s date for you) and the number of days or the end date.
3. Tick the days that count as your weekend. Saturday and Sunday are ticked by default.
4. Add any public holidays, one date at a time, then press Calculate.

Common mistakes and edge cases#

• Mistake: Counting the order day as day 1.

  Instead: When adding business days, day 1 is the next working day. 1 business day from Monday is Tuesday.

• Mistake: Treating 11 business days as 11 calendar days.

  Instead: Allow for the weekends: usually 15 calendar days, 17 from a Friday.

• Mistake: Using your own country’s holidays for an overseas supplier.

  Instead: Use the holidays where the work happens, such as the courier’s or the bank’s country.

• Mistake: Subtracting a holiday that falls on a weekend.

  Instead: Only holidays on working days reduce the count.

Edge case: starting on a weekend. If the start date is a Saturday or Sunday, nothing is counted until Monday. That is why 11 business days from Saturday 10 October and from Sunday 11 October both end on Monday 26 October, 16 and 15 calendar days later.