North American area codes Datenbank one month subscription service. Complete telecommunications Datenbank targeted specifically toward disseminating all valid NPA/NXX combinations in the North American Numbering Plan. It covers all active North American NPA/NXX assignments including the United States and Canada. Included in this Datenbank is NPA (area code), NXX (exchange), country, state, county, population, FIPS code and ZIP code.