A leap year starting on Saturday is any year with 366 days (i.e. it includes 29 February) that begins on

Saturday Saturday is the day of the week between Friday and Sunday. No later than the 2nd century, the Romans named Saturday ("Saturn's Day") for the planet Saturn, which controlled the first hour of that day, according to Vettius Valens. The day's ...

, 1 January, and ends on

Sunday Sunday is the day of the week between Saturday and Monday. In most Western countries, Sunday is a day of rest and a part of the weekend. It is often considered the first day of the week. For most observant adherents of Christianity, Sunday ...

, 31 December. Its dominical letters hence are BA. The most recent year of such kind was

2000 File:2000 Events Collage.png, From left, clockwise: Protests against Bush v. Gore after the 2000 United States presidential election; Heads of state meet for the Millennium Summit; The International Space Station in its infant form as seen from ...

and the next one will be

2028 Predicted and scheduled events * January 1 – Books, films, and other works published in 1932 will enter the public domain in the United States. * January 12 – Partial lunar eclipse. * January 26 – Small annular solar eclip ...

in the

Gregorian calendar The Gregorian calendar is the calendar used in most parts of the world. It was introduced in October 1582 by Pope Gregory XIII as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years di ...

or, likewise

2012 File:2012 Events Collage V3.png, From left, clockwise: The passenger cruise ship Costa Concordia lies capsized after the Costa Concordia disaster; Damage to Casino Pier in Seaside Heights, New Jersey as a result of Hurricane Sandy; People gather ...

and

2040 In contemporary history, the third millennium of the anno Domini or Common Era in the Gregorian calendar is the current millennium spanning the years 2001 to 3000 ( 21st to 30th centuries). Ongoing futures studies seek to understand what is l ...

in the obsolescent

Julian calendar The Julian calendar, proposed by Roman consul Julius Caesar in 46 BC, was a reform of the Roman calendar. It took effect on , by edict. It was designed with the aid of Greek mathematics, Greek mathematicians and Ancient Greek astronomy, as ...

. In the

, years divisible by 400 are always leap years starting on Saturday. The most recent such occurrence was

and the next one will be

2400 In contemporary history, the third millennium of the anno Domini or Common Era in the Gregorian calendar is the current millennium spanning the years 2001 to 3000 (21st to 30th centuries). Ongoing futures studies seek to understand what ...

, see below for more. Any leap year that starts on Tuesday, Friday or

has only one Friday the 13th: the only one in this leap year occurs in October. Common years starting on Sunday share this characteristic, but also have another in January. From August of the common year preceding that year until October in this type of year is also the longest period (14 months) that occurs without a Friday the 13th. Common years starting on Tuesday share this characteristic, from July of the year that precedes it to September in that type of year. In this leap year, Martin Luther King Jr. Day is on

January 17 Events Pre-1600 *38 BC – Octavian divorces his wife Scribonia and marries Livia Drusilla, ending the fragile peace between the Second Triumvirate and Sextus Pompey. *1362 – Saint Marcellus' flood kills at least 25,000 people o ...

Valentine's Day Valentine's Day, also called Saint Valentine's Day or the Feast of Saint Valentine, is celebrated annually on February 14. It originated as a Christian feast day honoring one or two early Christian martyrs named Saint Valentine and, throu ...

is on a

Monday Monday is the day of the week between Sunday and Tuesday. According to the International Organization for Standardization's ISO 8601 standard, it is the first day of the week and in countries that adopt the "Sunday-first" convention, it is ...

, Presidents Day is on its latest possible date,

February 21 Events Pre-1600 *452 or 453 – Severianus, Bishop of Scythopolis, is martyred in Palestine. *1245 – Thomas, the first known Bishop of Finland, is granted resignation after confessing to torture and forgery. * 1440 – The ...

, the leap day is on a Tuesday,

Saint Patrick's Day Saint Patrick's Day, or the Feast of Saint Patrick ( ga, Lá Fhéile Pádraig, lit=the Day of the Festival of Patrick), is a cultural and religious celebration held on 17 March, the traditional death date of Saint Patrick (), the foremost patr ...

is on a Friday,

Memorial Day Memorial Day (originally known as Decoration Day) is a federal holiday in the United States for mourning the U.S. military personnel who have fought and died while serving in the United States armed forces. It is observed on the last Monda ...

is on

May 29 Events Pre-1600 * 363 – The Roman emperor Julian defeats the Sasanian army in the Battle of Ctesiphon, under the walls of the Sasanian capital, but is unable to take the city. *1108 – Battle of Uclés: Almoravid troops under ...

Juneteenth Juneteenth is a federal holiday in the United States commemorating the emancipation of enslaved African Americans. Deriving its name from combining "June" and "nineteenth", it is celebrated on the anniversary of General Order No. 3, ...

is on a

U.S. Independence Day Independence Day ( colloquially the Fourth of July) is a federal holiday in the United States commemorating the Declaration of Independence, which was ratified by the Second Continental Congress on July 4, 1776, establishing the United Sta ...

is on a Tuesday,

Labor Day Labor Day is a federal holiday in the United States celebrated on the first Monday in September to honor and recognize the American labor movement and the works and contributions of laborers to the development and achievements of the United ...

is on September 4,

Thanksgiving Thanksgiving is a national holiday celebrated on various dates in the United States, Canada, Grenada, Saint Lucia, Liberia, and unofficially in countries like Brazil and Philippines. It is also observed in the Netherlander town of Leiden ...

is on November 23, and

Christmas Christmas is an annual festival commemorating the birth of Jesus Christ, observed primarily on December 25 as a religious and cultural celebration among billions of people around the world. A feast central to the Christian liturgical year ...

is on a

. This is the only type of year in which all dates (except 29 February) fall on their respective weekdays the minimal 56 times in the 400 year Gregorian Calendar cycle. Additionally, these types of years are the only ones which contain 54 different calendar weeks (2 partial, 52 in full) in areas of the world where Sunday is considered the first day of the week, and also the only type of year to contain 53 full weekends.

Calendars

Applicable years

Gregorian Calendar

Leap years that begin on Saturday, along with those that start on Monday or

Thursday Thursday is the day of the week between Wednesday and Friday. According to the ISO 8601 international standard, it is the fourth day of the week. In countries which adopt the "Sunday-first" convention, it is the fifth day of the week. Name ''Se ...

, occur least frequently: 13 out of 97 (≈ 13.402%) total leap years in a 400-year cycle of the

. Their overall occurrence is thus 3.25% (13 out of 400). 400 year cycle century 1: 028, 056, 084 century 2: 124, 152, 180 century 3: 220, 248, 276 century 4: 316, 344, 372, 400

Julian Calendar

Like all leap year types, the one starting with 1 January on a Saturday occurs exactly once in a 28-year cycle in the Julian calendar, i.e. in 3.57% of years. As the Julian calendar repeats after 28 years that means it will also repeat after 700 years, i.e. 25 cycles. The year's position in the cycle is given by the formula ((year + 8) mod 28) + 1).

References

{{DEFAULTSORT:Leap Year Starting On Saturday Gregorian calendar Julian calendar Saturday