Filothea’s name day is February 19, the feast of Philothei of Athens.
Churches that follow the Old (Julian) Calendar keep the same feast on March 4 (a day earlier in leap years) of the civil calendar. See everything commemorated on February 19.
The saint behind the name
Philothei of Athens
February 19, Holy Woman, Φιλοθέη η Αθηναία
St. Philothei was born in Athens in the sixteenth century to a noble family, and after the death of her husband devoted herself and her wealth to God. She founded a convent dedicated to St. Andrew in Athens, together with schools, hospices and workshops, and ransomed Christian women from Turkish captivity.
Also celebrating on February 19
These names share the feast, many of them other forms of the same name:
Philothei, Filothei, Philothea
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.