Week 13 2026: March 23–29, 2026
Week 13 starts on Monday, March 23, 2026 and ends on Sunday, March 29, 2026.
Quick answer
Week 13 of 2026 is the seven-day ISO week from March 23, 2026 to March 29, 2026. ISO weeks always run from Monday to Sunday.
Use week 13 in professional planning
This permanent week reference can be used in project plans, payroll notes, weekly reports, production schedules and deadline documents. Share the week number together with the ISO year and exact date range to avoid ambiguity around New Year.
For calculations that span more than one week, use the weeks between dates calculator. For work schedules, compare the same range with the business days calculator or open the project timeline calculator.
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FAQ
What are the dates for week 13 of 2026?
The dates are March 23, 2026 through March 29, 2026.
What day does this week start?
It starts on Monday.
What day does this week end?
It ends on Sunday.
How should I write this week in a report?
Use “ISO week 13 of 2026 (Mar 23–Mar 29, 2026)” so the week-year and date range are both clear.