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Timezones

Whenever you need to specify a timezone argument for a date/time function, or if you need to include a timezone in a date/time text, you can specify any of the supported timezone IDs (see below) or simply specify an offset from GMT.

GMT Offset

To specify a simple GMT offset, use either "GMT+HH:MM" or "GMT-HH:MM", where you replace "HH" and "MM" with the correct two-digit hour and minute values for the desired offset from GMT. Or simply use "GMT" for a zero offset. For example for an offset of +6 hours, you would use "GMT+06:00".

But note that this defines a plain offset from GMT, without regards to potential daylight saving time changes. To make sure that daylight saving time is taken into account too, you should instead specify a real timezone ID, as explained below.

Timezone IDs

If you want to specify a timezone ID, for example to make sure that daylight saving time changes are correctly observed according to the rules of a specific timezone, then you must specify one of the IDs that are supported by LISTSERV Maestro.

Use the selection list in the table below to find out which timezone IDs are supported for a given GMT offset.

Note: Even though there are ususally several timezones that share the same offset, they are not always interchangable because even if they have the same offset from GMT, different timezones may have different daylight saving time rules. So you should pick the timezone that has both the correct offset from GMT and that matches your locale/country, so that it also takes your local daylight saving time rules into account. For example for the UK, you should not pick GMT (because GMT does not include daylight saving time) but instad "Europe/London" - unless of course you explicitely want to ignore daylight saving time changes.