Pamphilos’s name day is February 16, the feast of Pamphilos.
Churches that follow the Old (Julian) Calendar keep the same feast on March 1 of the civil calendar. See everything commemorated on February 16.
The saint behind the name

Pamphilos
February 16, Martyr, Πάμφιλος
St. Pamphilos was a priest of Caesarea in Palestine, a man of great learning who devoted his life to the study and careful copying of the Holy Scriptures and gathered a famous library for the Church. During the persecutions at the beginning of the fourth century he was imprisoned for his confession of Christ, and after a long captivity he was put to death together with a company of fellow martyrs.
Name days: Pamphilos
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.