IST(Irish Standard Time)
Irish Standard Time (IST) is the legal time of Ireland during the brighter half of the year, one hour ahead of UTC.
- UTC offset
- UTC+01:00
- Abbreviation
- IST
- Full name
- Irish Standard Time
- Military letter
- Alpha (A)
- Regions
- Ireland
- IANA zones
- Europe/Dublin
- Converter model
- Fixed offset.
What IST means
Irish law is unusual in defining this offset as the country's standard time rather than as an adjustment applied to it, which is why the abbreviation appears with a +1 offset.
- This is the reason a single abbreviation, IST, can mean an offset of +01:00 in Dublin, +02:00 in Israel and +05:30 in India.
- Use Europe/Dublin when Irish time matters in software.
Cities on this offset
These cities keep UTC+01:00 as their standard offset:
- Dublin
- Cork
- Galway
- Limerick
Other meanings of IST
IST is used for more than one time zone. This page describes Irish Standard Time; the other meanings have their own pages and their own offsets:
- IST — Israel Standard Time (UTC+02:00)
- IST — India Standard Time (UTC+05:30)
Zones with the same offset
- CET — Central European Time (UTC+01:00)
History
The Standard Time (Amendment) Act 1971 defined Irish Standard Time as one hour ahead of UTC, inverting the usual arrangement used by neighbouring countries.