Week 49 2025: December 1–7, 2025
Week 49 starts on Monday, December 1, 2025 and ends on Sunday, December 7, 2025.
Quick answer
Week 49 of 2025 is the seven-day ISO week from December 1, 2025 to December 7, 2025. ISO weeks always run from Monday to Sunday.
Use week 49 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 49 of 2025?
The dates are December 1, 2025 through December 7, 2025.
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 49 of 2025 (Dec 1–Dec 7, 2025)” so the week-year and date range are both clear.