Is Christmas day a holiday in South Korea?

Korea is nearly 50% Christian, thanks to missionaries post WW2. They celebrate Christmas as the birth of christ and tend to skip all the commercialism I so enjoyed when I lived in the states. Last year, we took my daughter to Singapore to visit with Santa and see a reindeer show. These things are not common in Seoul.
Christmas Day and eve are also seen more as a couples holiday than a family. A couple might go out and walk through the holiday lights in downtown Seoul and have a "happy love" dinner. these dinners, dreamed up by savy restauranteurs and their version of Christmas commercialism. But families would not all unite for a holiday dinner the way they would for Chusoek. (Korean Thanksgiving)
churches are widely attended on Christmas Day.

December 24th is day everywhere.

Only for the South Koreans.

Certainly Christmas is a celebration of the birth of Christ. Anywhere Christan live there is cause for celebration

yup....it's a red day on the calendar....although some companies it's only on that day......after that it's a regular work day again.....sucks but true....but if you a longer holiday work in an english institute, some lasts for 5 days others just 3.....

Yes, it is. If you live in a major city in Korea, you can't walk a block without hearing "Last Christmas" by Wham!

Yes, Christmas day is a national holiday. The kids are out of school and some places close. A lot of places stay open though, more than would in western countries.