How Many Days Until the Winter Solstice 2029?

the Winter Solstice 2029 is Friday, 21 December 2029

There are 1,211 days between 28 August 2026 and the Winter Solstice 2029, which falls on Friday, 21 December 2029. That is exactly 173 weeks, or 828 working days once Saturdays, Sundays and the US federal holidays in between are taken out — the figure that matters if you are counting delivery lead time or a work schedule rather than sleeps. The date is 2029-12-21 in ISO form and 12/21/2029 in the US format, it falls in ISO week 51 of 2029, and it is day 355 of 365.

How the date of the Winter Solstice is decided

The December solstice, the shortest day in the northern hemisphere, falling on 21 or 22 December.

That makes it a computed date: there is no fixed day and no simple weekday rule, so it has to be worked out from a formula or a calendar of its own each year. In 2029 it works out as Friday 21 December.

the Winter Solstice is an observance rather than a federal holiday. Offices, banks and schools stay open unless an individual employer chooses otherwise, and it counts as an ordinary business day in every calculator here. Only the eleven federal holidays are treated as non-working days — the list and the reasoning are on the holiday sources page.

the Winter Solstice in the years after 2029

Both the date and the weekday move, because the rule is not tied to either.

Every convention used above — whether the start date counts, how month ends are clamped, which holidays close an office — is written out on the methodology page, including how we count the 828 working days above.