When is Christmas?

Why is Christmas on December 25?

The date of December 25 for Christmas was established by the early Christian church in Rome during the 4th century. The earliest recorded Christmas celebration on this date appears in the Chronograph of 354 AD, a Roman almanac. Pope Julius I is traditionally credited with officially designating December 25 as the birth date of Jesus, though historical records are incomplete.

Scholars believe the church chose December 25 in part to coincide with existing Roman winter festivals. The Roman feast of Saturnalia ran from December 17 to 23 — a week of feasting, gift-giving, and social inversion. December 25 was also celebrated in the Roman empire as the birthday of Sol Invictus (the Unconquered Sun), a solar deity. Placing Christmas near the winter solstice gave the new holiday a natural home at a time when Romans were already celebrating light returning to the world.

Another theory, proposed by historian Thomas Talley, is that early Christians calculated the date of the Annunciation (when Mary learned she would conceive Jesus) as March 25 — and counting nine months forward gives December 25. This theory, known as the "integral age" or "computation" hypothesis, argues the date arose from Christian calculation rather than assimilation of pagan festivals.

Is Christmas Always December 25?

For most of the world using the Gregorian calendar, Christmas is always December 25. However, some Orthodox Christian churches follow the older Julian calendar, which is currently 13 days behind the Gregorian calendar.

Most Eastern Orthodox Christians (in Russia, Serbia, Ethiopia, and parts of the Middle East) celebrate Christmas on January 7 — which corresponds to December 25 on the Julian calendar. The Armenian Apostolic Church, one of the oldest Christian churches in the world, celebrates Christmas on January 6 — combined with the Feast of the Epiphany. The Ethiopian Orthodox Church (Tewahedo) also celebrates on January 7, known locally as Genna.

Some Orthodox churches — including those in Greece, Romania, Bulgaria, and the Antiochian Orthodox — have adopted the Revised Julian Calendar and celebrate Christmas on December 25 alongside the Western church.

Christmas Eve: December 24

Christmas Eve is December 24 — the evening immediately before Christmas Day. In many Christian traditions, the feast of Christmas actually begins at sunset on December 24, following ancient Jewish liturgical practice where days run from evening to evening. This is why Midnight Mass on Christmas Eve is considered the opening celebration of Christmas.

In several European countries — including Germany, Austria, Switzerland, Scandinavia, and much of Latin America — Christmas Eve is the primary night of celebration. Gifts are opened, families feast together, and church services are held on the night of December 24, with December 25 being a quieter day of rest. In Germany this tradition is called Heiligabend (Holy Evening).

Christmas Dates 2025–2029

Christmas Day is always December 25, but the day of the week changes each year:

Frequently Asked Questions