Why holidays like Easter, Diwali and Eid move every year

Some holidays are fixed dates, some are weekday rules, and many follow the moon through another calendar. Each kind moves in its own way.

Published by Sumit Teli

Every holiday below has its own live countdown, such as the Easter countdown, with the dates for the coming years. For any other date, use the countdown to a date.

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Three kinds of holiday date

Holidays are set in one of three ways, and only the first kind stays on the same date every year:

KindExamplesHow much it moves
A fixed date in the Gregorian calendarChristmas (Dec 25), New Year's Day, Halloween, July 4Never; only the weekday changes
A weekday ruleUS Thanksgiving, Mother's Day, Memorial Day, Labor DayWithin a 7-day window
The moon, through another calendarEaster, Ramadan, Eid, Chinese New Year, Diwali, HanukkahBy weeks, or right through the year

A fixed date moves one weekday later each year, or two after a February 29, because 365 days is 52 weeks and 1 day. That is why Christmas 2026 is on a Friday and Christmas 2027 on a Saturday.

Weekday rules: the same day of the week, a different date

Many holidays are set as “the nth weekday of a month” so that they always fall on the same day of the week. US Thanksgiving is the fourth Thursday of November, so it can be any date from November 22 to 28. Mother's Day in the US and many other countries is the second Sunday of May (May 8 to 14), and Father's Day the third Sunday of June (June 15 to 21).

A “last weekday” rule works the same way from the end of the month: Memorial Day is the last Monday of May, May 25 to 31. Holidays that hang off another one move with it: Black Friday is the day after Thanksgiving and Cyber Monday four days after.

Many of these rules come from laws. The US Uniform Monday Holiday Act of 1968 moved several federal holidays, including Memorial Day and Washington's Birthday, to Mondays from 1971, so that they make long weekends.

Easter: a moon date worked out in advance

Easter Sunday is the first Sunday after the Paschal full moon, which is the first church full moon on or after March 21. The churches don't look at the real moon. They use fixed tables, known as the computus, that predict it closely enough, and they treat March 21 as the spring equinox every year. That makes Easter computable for any year, and it always falls between March 22 and April 25.

The full moon falls about 11 days earlier against the calendar each year, because 12 lunar months are about 354 days, then jumps back by a month. Easter jumps with it: March 28 in 2027, then April 16 in 2028.

Other dates follow Easter: Good Friday two days before, Mothering Sunday in the UK three weeks before, and Ash Wednesday 46 days before. Orthodox churches use the same rule with the older Julian calendar, so their Easter is the same day or one to five weeks later.

Ramadan and Eid: a purely lunar calendar

The Islamic calendar has 12 lunar months and no leap month, so its year is 354 or 355 days, about 11 days shorter than the solar year. Every Islamic date, including the start of Ramadan, Eid al-Fitr and Eid al-Adha, comes about 11 days earlier each year and moves through all the seasons in about 33 years. In 2030, Ramadan begins twice: in early January and again in late December.

Each month begins when the new crescent moon is seen after sunset. Many countries and communities wait for an actual sighting, which is why Eid al-Fitr is often confirmed only on the evening before, and why it can be on different days in different countries. Saudi Arabia publishes the Umm al-Qura calendar, calculated in advance, which is what most published future dates are based on.

Chinese New Year, Diwali and Hanukkah: lunar months kept in their season

These calendars also count months by the moon, but add a leap month every two or three years so the festivals stay in the same season. The date wanders back and forth within a window of about a month instead of moving right through the year.

  • Chinese New Year is the new moon that starts the first month, between January 21 and February 20. The moment of the new moon is judged in China's time zone.
  • Diwali falls on Amavasya, the new-moon day of the Hindu month of Kartika, in October or November. Hindu calendars count lunar days (tithis) that start at any time of day, so the festival is held on the day the new moon covers the evening where you are. In some years that makes it a day earlier in the Americas than in India.
  • Hanukkah starts on the 25th of Kislev in the Hebrew calendar, which adds a leap month seven times every 19 years. The Hebrew calendar is fully calculated, so its dates are known years ahead. The first candle is lit on the evening before, since Jewish days begin at sundown.

The dates from 2026 to 2030

YearEasterChinese New YearRamadan beginsEid al-FitrDiwaliHanukkah begins
2026Apr 5Feb 17Feb 18Mar 20Nov 8Dec 4
2027Mar 28Feb 6Feb 8Mar 9Oct 29Dec 24
2028Apr 16Jan 26Jan 28Feb 26Oct 17Dec 12
2029Apr 1Feb 13Jan 16Feb 14Nov 5Dec 1
2030Apr 21Feb 3Jan 5 and Dec 26Feb 4Oct 26Dec 20

Ramadan and Eid dates are the expected dates in the Umm al-Qura calendar and can be a day later where the moon is sighted later. Diwali dates are for India. Hanukkah begins at sundown on the date shown.

Planning around a moving holiday

  • Check the year, not last year's date. Easter, Eid and Diwali can be weeks apart from one year to the next.
  • For Islamic holidays, keep a day spare. Book time off for the expected date and the day after until the moon sighting is announced.
  • Use local dates. Diwali, Eid and even Chinese New Year can fall on a different day in another country. Your local temple, mosque or community calendar has the final word.
  • Mind the evening start. Islamic and Jewish holidays begin at sunset the evening before the date on the calendar.
  • Counting working days? Holidays push business-day deadlines later. See the guide to business days and calendar days, or the Diwali countdown for the working days left.

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