Week 43 2025: October 20–26, 2025
Week 43 starts on Monday, October 20, 2025 and ends on Sunday, October 26, 2025.
Quick answer
Week 43 of 2025 is the seven-day ISO week from October 20, 2025 to October 26, 2025. ISO weeks always run from Monday to Sunday.
Use week 43 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 43 of 2025?
The dates are October 20, 2025 through October 26, 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 43 of 2025 (Oct 20–Oct 26, 2025)” so the week-year and date range are both clear.