Australia used Official Stamps with ‘OS’ perforated on them from 1913 (when postage stamps were first issued) until 1930. From 1930 to 1933, ‘OS’ overprints were used rather than perfins.
Although intended mostly for use among governmental agencies, Australia’s official stamps were valid for any type of postage. Covers and blocks of OS stamps from Australia are appealing to many stamp collectors.
Check the current listings of Australia official ‘OS’ postage stamps for sale in the marketplace. Note that the offers are updated and reviewed every day. These listings may include both OS perfins and overprints.
