The Mystery of Australian Time

As I was browsing the internet last week, I stumbled across this post on Reddit highlighting the five official time zones of Australia:

As someone who has had to deal with comparatively easy one hour time zone increments in the United States, this image made me cringe. The comments in the post made me aware of something even more strange than the time zone map above…

Australia Has a Secret Time Zone

Ok, not really secret but still unofficial. The time zone is called “Australia – Central Western Standard Time” and is the time zone used on the Eyre Highway that runs in Western Australia and South Australia. You’ll be greeted by a sign informing you to turn your clock forward 45 minutes when entering:

Changing one hour forward or one hour backward can be a hassle. Half hour increments seems unnecessary. 45 minute increments? Just plain confusing.

Recognized by SQL Server?

Since the time zone is not official, I wondered whether or not it would be included in SQL Server. I queried sys.time_zone_info to find out:

SELECT * FROM sys.time_zone_info
WHERE current_utc_offset = '+08:45';
GO

It exists! Comparing with my current time in Eastern Standard Time:

SELECT SYSDATETIMEOFFSET() AT TIME ZONE 'Eastern Standard Time' AS 'Eastern';
GO
SELECT SYSDATETIMEOFFSET() AT TIME ZONE 'Aus Central W. Standard Time' AS 'Aus Central W. Standard Time';
GO

Out of curiosity, I checked to see if that was the only time zone not in hourly or half hour increments:

SELECT * FROM sys.time_zone_info
WHERE current_utc_offset LIKE '%45';
GO

It turns out Nepal Standard Time in Nepal and Chatham Islands Standard Time in New Zealand also fit the 45 offset criteria.

You’re Ready for Jeopardy

The next time you’re scheduling a meeting with someone in a different time zone or changing a clock due to daylight saving time, remember Australia and their unofficial Central Western Standard Time.

Thanks for reading!