Between 1966 and 1970, the Australian Post Office did not issue official first day covers.
However in 1964, Philatelic Sales Sections made available general first day covers for the use of any new issue Australian postage stamps. The covers were available at 3d each in two sizes: 10.5cm x 5.6cm and 22.86cm x 10.16cm. They were printed in two designs and in four colours: silver grey, Wedgwood blue, pastel stone and olive grey.
In 1970, official first day covers became available with the Expo 70 stamp issue.