Week 40 of 2027 runs October 4, 2027 to October 10, 2027.
Week 40 starts on Monday, October 4, 2027 and ends on Sunday, October 10, 2027. It's the 277th day of the year, sits in Q4, and falls in October. By the end of this week, 283 of 365 days are gone, putting 2027 at 77.5%.
There are no public holidays this week, so all 5 weekdays are working days. Need a different week? Browse the full 2027 week calendar, or jump to this week's number.
Week 40 at a glance
The 7 days of week 40
Every date in week 40 of 2027, Monday through Sunday, with day-of-year numbers and events.
| Day | Date | Day no. | Type | Events |
|---|---|---|---|---|
| Monday | Day 277 | Weekday | ||
| Tuesday | Day 278 | Weekday | ||
| Wednesday | Day 279 | Weekday | ||
| Thursday | Day 280 | Weekday | ||
| Friday | Day 281 | Weekday | ||
| Saturday | Day 282 | Weekend | ||
| Sunday | Day 283 | Weekend |
What week 40 of 2027 means
ISO 8601 numbers weeks so every week starts on Monday and ends on Sunday. Week 1 is the one holding the year's first Thursday, which is why early January can land in week 52 or 53 of the previous year. Week 40 is one piece of that system.
In 2027, week 40 covers Oct 4 – Oct 10, 2027. That's October, deep in Q4. The same week number shifts by a day or two each year, so week 40 in 2028 won't share these exact dates. The table below shows how it moves.
Want to check a specific date instead of a week number? The week calculator converts any date to its ISO week. Curious how many weeks a year holds? The weeks in a year guide explains 52 versus 53. And the ISO week number page covers the standard end to end.
Holidays in week 40 of 2027
No major public holidays in week 40 of 2027 across the US, UK, Canada, or Australia.
Week 40 across years
The same ISO week number lands on different dates each year. Here's how week 40 shifts.
Week 40 of 2027: questions and answers
What days are in week 40 of 2027?
Week 40 of 2027 runs from October 4, 2027 (Monday) through October 10, 2027 (Sunday). It spans October.
What month is week 40 in 2027?
Week 40 of 2027 falls entirely in October 2027.
How many working days are in week 40 of 2027?
Week 40 of 2027 has 5 working days.
What quarter is week 40 of 2027 in?
Week 40 of 2027 is in Q4 (2027). The week starts on day 277 of 365.
What is ISO week 40?
ISO week 40 is defined by the ISO 8601 international standard. It begins on Monday, October 4, 2027, and ends on Sunday, October 10, 2027. It is week 77% through the ISO year 2027.