Euthasia’s name day is January 12, the feast of Euthasia the Martyr.
Churches that follow the Old (Julian) Calendar keep the same feast on January 25 of the civil calendar. See everything commemorated on January 12.
The saint behind the name
Euthasia the Martyr
January 12, Holy Woman, Ευθασία
St. Euthasia is commemorated on January 12 as a holy woman martyr. The synaxaria preserve her name and confession, but the details of her life and contest have not survived.
Also celebrating on January 12
These names share the feast, many of them other forms of the same name:
What to say on a name day
The Greek wish is Χρόνια Πολλά (Chronia Polla), “many years.” A call or a short message on the day is what people remember. See name day wishes you can send and what a name day is.