ISO week 2027-W39

Week 39, 2027

Monday, September 27 – Sunday, October 3, 2027

ISO week 39 of 2027 (2027-W39) runs from Monday, September 27, 2027 to Sunday, October 3, 2027.

This week starts 50 weeks from now. The current week is week 42, 2026.

The 7 days of week 39

Dates in week 39, 2027
Day	Date	Day of year	US week	ISO date
Monday	September 27, 2027	270 of 365	40	2027-W39-1
Tuesday	September 28, 2027	271 of 365	40	2027-W39-2
Wednesday	September 29, 2027	272 of 365	40	2027-W39-3
Thursday	September 30, 2027	273 of 365	40	2027-W39-4
Friday	October 1, 2027	274 of 365	40	2027-W39-5
Saturday	October 2, 2027	275 of 365	40	2027-W39-6
Sunday	October 3, 2027	276 of 365	41	2027-W39-7

Week 39 at a glance

ISO code: 2027-W39 (Monday is 2027-W39-1, Sunday is 2027-W39-7)
Month: September and October
Quarter: Q3 by the ISO rule (its Thursday, September 30, is in Q3); the calendar dates span Q3 and Q4
Day of year: Days 270–276 of 365
US week number: Monday–Saturday: US week 40; Sunday: US week 41 (Sunday-start weeks, week 1 contains January 1)
Even or odd: Week 39 is an odd week
Weeks left: After this week, 13 ISO weeks remain in 2027 (52 weeks in total)
Year progress: By Sunday, 76% of 2027 has passed

Holidays and key dates

Friday, October 1: Q4 begins

Week numbers follow ISO 8601: weeks start on Monday and week 1 contains the first Thursday of the year. US weeks start on Sunday, with week 1 containing January 1.

Questions about week 39, 2027

What are the dates of week 39 in 2027?

Week 39 of 2027 starts on Monday, September 27, 2027 and ends on Sunday, October 3, 2027.

What month is week 39 of 2027?

Week 39 falls in September and October. By the Thursday rule that ISO 8601 uses for years and quarters, it counts as a September week.

How do I get week 39 of 2027 in Excel or Google Sheets?

=ISOWEEKNUM(DATE(2027,9,27)) returns 39. To go the other way, =DATE(2027,1,4)-WEEKDAY(DATE(2027,1,4),2)+1+(39-1)*7 returns the Monday, September 27, 2027.