St. Helena Business Directory: SHN is the ISO 3 alphabet country code of St. Helena. Currency of St. Helena is £, which has a short code of SHP. Capital of St. Helena is Jamestown. St. Helena has the population of 4074 and approximate area is 122.00 square kilometers (or approx. 75.8108 square miles). Population density of St. Helena is approx. 33/Km2 (or approx. 20.5062/mile2)