San Nicolas, officially the Municipality of San Nicolas, is a municipality in the province of Ilocos Norte, Philippines. According to the 2020 census, it has a population of 38,895 people. The present name of San Nicolas was given in the year 1733, after Saint Nicholas of Tolentino, who was believed to have protected the people against floods, earthquakes, fires, typhoons and other calamities. It is significant that in Ilocos Norte, only San Nicolas was named after a saint.