School holidays are the periods during which schools are closed for study. The dates and periods of school holidays vary considerably throughout the world, and there is usually some variation even within the same jurisdiction. Governments often legislate on the total number of school days for state schools. The holidays given below apply to primary and secondary education. Teaching sessions in Tertiary education are usually shorter.

In the United States, there are normally 180 school days in a year(though college and university years are often shorter).

Private schools tend to be 170 days a year, but sometimes more or less. Public schools from grades K-12 may have the following breaks/holidays:

• Autumn (Fall) Break - About one week in October (in the week of Columbus Day) (some areas do not have this break, these areas only take Columbus Day itself off)
• Thanksgiving Holiday - End of November (The week of Thanksgiving - 3 days before Thanksgiving, Thanksgiving Day, and the day after - the Friday before the break is sometimes considered a half-day - some areas use variations or do not have this break). Some areas have the Monday and Tuesday of the Thanksgiving week as regular days and take Wednesday as a half-day; with Thanksgiving and the day after off.
• Christmas/Holiday Break - Varies, usually starts the third Saturday in December and ends the first Monday after the New Year's Day, unless New Year's Day falls on a Sunday in which the first Monday is the official holiday, so school would re-open on the Tuesday after New Year's Day, as was the case in 2012.
• Martin Luther King Break - Students have a full or half-day Friday and have the Weekend, Martin Luther King day, and sometimes Tuesday off.
• Winter Break - One week in February or March (depending on the region, and some areas do not have this break)
• Easter/Spring Break - 1 to 2 weeks in March or April (usually starting on Lazarus Saturday).
• Summer Break - About 10 to 12 weeks (either from late May to late August, or early June to the day after Labor Day in early September - depending on the region and state).
• All federal and state holidays, including religious holidays (such as Good Friday, and sometimes Jewish/Islamic holidays) - depending on school demographic.
• Teacher's Day off (convention) - 2 to 3 days on any day in school calendar.
• Snow Days (in regions where it snows in winter) - Usually a few days up to a full week allocated. Where these exceed the allocation, they are made up from scheduled breaks (such as mid-winter break), or made up with days at the end of the school year.

Colleges and universities vary widely. Some closely follow the K-12 break schedule, others have the same but longer breaks to accommodate students who live farther away and wish to return home for holidays. Most colleges and universities have the following breaks/holidays:

• Thanksgiving Holiday - End of November (The week of Thanksgiving - 3 days before Thanksgiving, Thanksgiving Day, and the day after - the Friday before the break is considered a half-day).
• Christmas/Holiday Break - mid-December to late January
• Spring Break - a week in March or April (usually starting on Good Friday)
• Summer Break - Early May to the day after Labor Day in September
• Snow Days (In regions where it snows in winter) - usually a few days up to a full week, and no days to make up.

Most colleges and university years are divided into two semesters. The first starting from day after Labor Day in early September until mid-December, and the second lasting from the end of January until early May. Winter and summer classes could be taken in between the breaks.