The monthly mean minimum and maximum temperatures over the year in Stockholm, Sweden. Show the average temperatures in Stockholm in Celsius Â» Data from nearest weather station: Stockholm, Sweden (0.0 Miles).
The postal service started the use of postal zones for large cities in 1943. By the early 1960s a more general system was needed. On July 1, 1963, ZIP codes were created for the whole country but they were not mandatory. In 1967, these were made mandatory for many types of mail. The system was soon used for all mail.
What year zip codes started?   ZIP Code began on July 1, 1963. Use of the new code was not mandatory at first for anyone, but, in 1967, the Post Office required mailers of second- and third-class bulkâ¦ mail to presort by ZIP Code.