Week 52 of 2026 runs December 21 to December 27

ISO week 52 of 2026 begins on Monday, December 21, 2026 and ends on Sunday, December 27, 2026. It starts in 89 days, about 13 weeks from the current week 39. The week covers December only.

What dates are in week 52?

Week 52 of 2026 contains December solstice on December 21 and Christmas Eve on December 24 and Christmas Day on December 25. The seven dates always run Monday through Sunday, which is the part of ISO 8601 that most often catches people out: a week that starts on Sunday is a different convention and gives a different number.

How ISO week 52 is worked out

ISO 8601 fixes week one as the week containing the first Thursday of January, which is the same as saying the week containing 4 January, or the week holding the majority of its days in the new year. Counting forward from there, week 52 is the 52nd Monday-to-Sunday block of 2026, which lands on December 21. All seven dates sit inside 2026, so the ISO year and the calendar year agree for this week.

When is week 52 in other years?

Week 52 shifts by a day or two each year because a year is 52 weeks plus one or two days, so the Monday that opens it moves from December 21 in 2026 to December 27 in 2027.

How far away is week 52?

Today is Wednesday, September 23, 2026, which sits in ISO week 39 of 2026. Week 52 of 2026 opens in 89 days, so there are roughly 13 weeks to go. Counting only complete weeks between now and then gives 12.

Questions

What dates are in week 52 of 2026?

Monday December 21, 2026 through Sunday December 27, 2026.

What week is it now?

ISO week 39 of 2026. Today is Wednesday, September 23, 2026.

How many weeks does 2026 have?

53. The 2026 week count page explains the rule.

Do ISO weeks start on Monday or Sunday?

Monday. A Sunday-first week is a different convention and can give a different week number for the same date.

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