The Ge'ez calendar (Ge'ez: ዓዉደ ወርህ; Tigrinya: ዓዉደ ኣዋርሕ; Amharic: የኢትዮጲያ ዘመን ኣቆጣጠር) is the principal calendar used in Ethiopia and Eritrea, which also serves as the liturgical year for Christians in Ethiopia and Eritrea belonging to the Orthodox Tewahedo Churches (Ethiopian Orthodox Tewahedo Church and Eritrean Orthodox Tewahedo Church), Eastern Catholic Churches (Eritrean Catholic Church and Ethiopian Catholic Church), and Eastern Protestant Christian P'ent'ay (Ethiopian-Eritrean Evangelical) Churches (most Protestants in the diaspora have the option of choosing the Ge'ez calendar or the Gregorian calendar for religious holidays, with this option being used when the corresponding eastern celebration is not a public holiday in the western world). The Ge'ez calendar is a solar calendar that has more in common with the Coptic calendar of the Coptic Orthodox Church of Alexandria and Coptic Catholic Church, but like the Julian calendar, it adds a leap day every four years without exception, and begins the year on August 29 or August 30 in the Julian calendar. A gap of seven to eight years between the Ge'ez and Gregorian calendars results from an alternative calculation in determining the date of the Annunciation.
This article needs additional citations for verification. (March 2021)
The Ge'ez calendar has twelve months of thirty days plus five or six epagomenal days, which comprise a thirteenth month. The Ge'ez months begin on the same days as those of the Coptic calendar, but their names are in Ge'ez. A sixth epagomenal day is added every four years, without exception, on August 29 of the Julian calendar, six months before the corresponding Julian leap day. Thus the first day of the Ge'ez calendar year, 1 Mäskäräm, for years between 1900 and 2099 (inclusive), is usually September 11 (Gregorian). It falls on September 12 in years before the Gregorian leap year, however.