Date and time notation in Australia


The date and time in Australia are most commonly recorded using the day–month–year format and the 12-hour clock, although 24-hour time is used in some cases. For example, some public transport operators such as V/Line and Transport for NSW use 24-hour time, although others use 12-hour time instead.

Date

Australians typically write the date with the day leading, as in the United Kingdom and in New Zealand:
The month–day–year order is occasionally used, often in the mastheads of magazines, newspapers, advertisements, video games, news, and TV shows; however, this is not an official standard and is often discouraged to avoid confusion. Month–day–year in numeric-only form is rarely used and also often discouraged.
The ISO 8601 date format is recommended by the government to be used when communicating internationally. It is also commonly used in software.
The Australian government identifies Monday as the first day of the week, which is consistent with the Common Locale Data Repository since its October 2021 release. However, there is disagreement among the general population over whether Monday or Sunday is the first day of the week.
Weeks are most identified by the last day of the week, either the Friday in business or the Sunday in other use. Week ending is often abbreviated to "W/E" or "W.E." The first day of the week or the day of an event are sometimes referred to. Week numbers are not often used, but may appear in some business diaries in numeral-only form. ISO 8601 week notation is not widely understood.

Time

The Australian government recommends using the 12-hour clock, except where the 24-hour clock is more helpful in the context, such as in travel, scientific fields and the military. The government also recommends a colon as the separator; however, the full stop is still used in some contexts. They also suggest writing the noon/after noon qualifier as "am" or "pm" in lower case without a full stop.