The official date for Christmas celebrations in Russia is the 6th of January. That is because the Russian Orthodox church decided to stay with the Julian calendar, while much of the rest of the world switched to the newer Gregorian. The official way to say “Merry Christmas” in Russian is “S rozhdyestvom Hristovym!”, which means “Congratulations on the birth of Christ!”. Since no one knows when exactly Jesus was born, there are quite a few Russians who start celebrating Christmas on December 24th and end on January 6th. You get to say “Merry Christmas” in Russian two times! There is also a much easier way to say “Merry Christmas” in Russian. You can use the universal “S prazdnikom!”, which is translated as “Happy holiday!”. But what is for certain is that your Russian friends and colleagues will really appreciate it if you take some pains and learn how to properly say “Merry Christmas” in Russian. About a month before the date you can see numerous banners, billboards and posters wishing everyone a Merry Christmas all over the place. And while it may take some effort on your part to remember the phrase at first, it really won’t be that hard. And of course, the most popular way to say it is "Schastlivogo Rozhdestva!", which is Russian for "Merry Christmas".