Week 13 of 2026
March 23 – March 29, 2026
| Monday | March 23, 2026 | Mon · week starts |
| Tuesday | March 24, 2026 | |
| Wednesday | March 25, 2026 | |
| Thursday | March 26, 2026 | |
| Friday | March 27, 2026 | |
| Saturday | March 28, 2026 | |
| Sunday | March 29, 2026 | Sun · week ends |
All weeks of 2026
2026 is an ISO year with 53 weeks.
About ISO week 13 of 2026
ISO 8601 weeks start on Monday and end on Sunday. Week 13 of 2026 begins on Monday, March 23, 2026 and ends on Sunday, March 29, 2026. Week numbering follows the international standard: week 1 of a year is the week containing the first Thursday of January, which is why some calendar dates near January 1st belong to the previous or next ISO year.
The ISO week system is the standard for business reporting across Europe and much of the world. The US convention differs: weeks start on Sunday and week 1 contains January 1st, so US week numbers can be one ahead of or behind ISO numbers near year boundaries.
Frequently asked questions
What dates are in week 13 of 2026?
Week 13 of 2026 spans March 23 – March 29, 2026: Monday March 23 through Sunday March 29.
When is week 13 of 2026?
Week 13 of 2026 started 218 days ago, on Monday, March 23, 2026.
Why does 2026 have 53 weeks?
2026 is a "long" ISO year with 53 weeks. This happens when the year starts on a Thursday, or on a Wednesday in a leap year — the extra days spill into a 53rd numbered week.