ISO week 2026-W12

Week 12, 2026

Monday, March 16 – Sunday, March 22, 2026

ISO week 12 of 2026 (2026-W12) runs from Monday, March 16, 2026 to Sunday, March 22, 2026.

This week ended 30 weeks ago. The current week is week 42, 2026.

The 7 days of week 12

Dates in week 12, 2026
Day	Date	Day of year	US week	ISO date
Monday	March 16, 2026	75 of 365	12	2026-W12-1
Tuesday	March 17, 2026	76 of 365	12	2026-W12-2
Wednesday	March 18, 2026	77 of 365	12	2026-W12-3
Thursday	March 19, 2026	78 of 365	12	2026-W12-4
Friday	March 20, 2026	79 of 365	12	2026-W12-5
Saturday	March 21, 2026	80 of 365	12	2026-W12-6
Sunday	March 22, 2026	81 of 365	13	2026-W12-7

Week 12 at a glance

ISO code: 2026-W12 (Monday is 2026-W12-1, Sunday is 2026-W12-7)
Month: March
Quarter: Q1 of 2026
Day of year: Days 75–81 of 365
US week number: Monday–Saturday: US week 12; Sunday: US week 13 (Sunday-start weeks, week 1 contains January 1)
Even or odd: Week 12 is an even week
Weeks left: After this week, 41 ISO weeks remain in 2026 (53 weeks in total)
Year progress: By Sunday, 22% of 2026 has passed

Holidays and key dates

There are no US federal holidays, daylight saving time changes or quarter starts in week 12 of 2026.

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 12, 2026

What are the dates of week 12 in 2026?

Week 12 of 2026 starts on Monday, March 16, 2026 and ends on Sunday, March 22, 2026.

What month is week 12 of 2026?

Week 12 falls in March. By the Thursday rule that ISO 8601 uses for years and quarters, it counts as a March week.

How do I get week 12 of 2026 in Excel or Google Sheets?

=ISOWEEKNUM(DATE(2026,3,16)) returns 12. To go the other way, =DATE(2026,1,4)-WEEKDAY(DATE(2026,1,4),2)+1+(12-1)*7 returns the Monday, March 16, 2026.