Some holidays never move: Independence Day is always July 4 and Christmas is always December 25. Others, often called floating holidays, are defined by a weekday rule such as "the fourth Thursday of November". Their calendar date shifts every year, but they always fall on the same day of the week, which conveniently creates long weekends.
The common floating-holiday rules
| Holiday (US) | Rule | Possible dates |
|---|---|---|
| Martin Luther King Jr. Day | Third Monday of January | Jan 15–21 |
| Presidents' Day (Washington's Birthday) | Third Monday of February | Feb 15–21 |
| Mother's Day | Second Sunday of May | May 8–14 |
| Memorial Day | Last Monday of May | May 25–31 |
| Father's Day | Third Sunday of June | Jun 15–21 |
| Labor Day | First Monday of September | Sep 1–7 |
| Columbus Day / Indigenous Peoples' Day | Second Monday of October | Oct 8–14 |
| Election Day | Tuesday after the first Monday of November | Nov 2–8 |
| Thanksgiving | Fourth Thursday of November | Nov 22–28 |
The pattern behind the "possible dates" column is simple: the first occurrence of any weekday must fall on days 1–7 of the month, the second on days 8–14, the third on 15–21 and the fourth on 22–28. "Last" can fall anywhere from the 25th to the 31st in a 31-day month.
The Uniform Monday Holiday Act
Several of these holidays used to fall on fixed dates. Washington's Birthday was celebrated on February 22, and Memorial Day (originally Decoration Day) on May 30. The Uniform Monday Holiday Act, passed by Congress in 1968 and effective in 1971, moved Washington's Birthday, Memorial Day and Columbus Day to Mondays, and also moved Veterans Day, so that federal workers would get more three-day weekends. Veterans Day proved the exception: because of its significance as the anniversary of the 1918 armistice, it was returned to its original November 11 date starting in 1978.
Thanksgiving's turbulent history
Thanksgiving became a national holiday in 1863, when President Abraham Lincoln proclaimed it for the last Thursday in November. In 1939, November had five Thursdays, and with the economy still recovering from the Great Depression, President Franklin D. Roosevelt moved Thanksgiving one week earlier to lengthen the Christmas shopping season. The change was unpopular in many states; some kept the old date, and critics nicknamed the new one "Franksgiving". In 1941 Congress settled the matter by law, fixing Thanksgiving on the fourth Thursday of November, which is why it can never be later than November 28.
Holidays that follow Thanksgiving
Because Thanksgiving floats, so do the shopping days tied to it: Black Friday is the following day and Cyber Monday is four days later. When Thanksgiving falls early, on November 22, the holiday shopping season is several days longer than when it falls on November 28.
How to work out the date yourself
- Find the weekday of the 1st of the month.
- Count forward to the first occurrence of the weekday you need.
- Add 7 days for each additional occurrence (second = +7, third = +14, fourth = +21).
- For "last", start from the last day of the month and count backwards to the weekday.
Example: November 1, 2026 is a Sunday. The first Thursday is November 5, so the fourth Thursday, Thanksgiving, is November 5 + 21 = November 26, 2026.
Floating holidays elsewhere
Other countries use the same idea. Canada's Thanksgiving is the second Monday of October; the United Kingdom's early May and spring bank holidays are the first and last Mondays of May; and many countries observe Mother's Day on the second Sunday of May, while the UK celebrates Mothering Sunday three weeks before Easter. Daylight saving time changes in the US also follow a weekday rule: the second Sunday of March and the first Sunday of November.
See this year's dates: every holiday's date and day of the week is listed on the holidays page, and each has a live countdown, for example Thanksgiving, Labor Day and Memorial Day.