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September 2028 Calendar

30 days, 21 of them working days. The number down the left is the ISO week; public holidays are not deducted, because which ones apply depends on where you are.

September30 days, 21 working
wkMoTuWeThFrSaSu
3528293031123
3645678910
3711121314151617
3818192021222324
392526272829301

What the week numbers mean

These are ISO 8601 weeks: every week runs Monday to Sunday and belongs to the year that owns its Thursday. It is why 1 January 2027 falls in week 53 of 2026, and why a year has 53 weeks whenever it starts on a Thursday or is a leap year starting on a Wednesday. The US business convention of numbering from 1 January gives different answers, and payroll systems disagree about which one they mean.

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