1960s ‘With Compliments’ slip showing the old post office sorting code for Spotswood W. 14 Vic. These codes were replaced by the current 4-digit post codes in 1967 by what was Australia Post’s predecessor, the Post Master General’s Department. The alpha numeric telephone codes were phased out during the 1960s, changing to numbers-only (7 digits) by 1971. STD code prefixes were added between 1971 and 1996, the 7 digit phone numbers were progressively changed to 8 digit numbers from 1996.
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