Alt St. Johann has a population () of 1466. , about 9.4% of the population was made up of foreign nationals. Of the foreign population, (), 19 are from Germany, 3 are from Italy, 91 are from ex-Yugoslavia, 8 are from Austria, and 37 are from another country.
Alt St. Johann has a population of 1466 people, with 9.4% being foreign nationals. Of the foreign residents, there are 19 from Germany, 3 from Italy, 91 from ex-Yugoslavia, 8 from Austria, and 37 from another country.