Europe/Istanbul

TZ identifier and aliases

Europe/Istanbul is the canonical identifier for Turkish civil time. Asia/Istanbul and the bare country name Turkey are older names still pointing at the same rules but are deprecated aliases — use Europe/Istanbul in new code, even though the city itself straddles both continents.

UTC offset and DST rule

Europe/Istanbul is +03:00 year-round with no daylight saving time. Turkey moved to permanent daylight time in September 2016 and made the change permanent by presidential decree in 2018 — so, like Russia, there's been no seasonal clock change here for years, but unlike Russia, Turkey settled on the "summer" offset rather than reverting to standard time.

Using it in cron, CI and Postgres

Set TZ=Europe/Istanbul for a process that should schedule by Turkish local time — naming the zone rather than hardcoding +03:00 keeps a config self-documenting and correct automatically if Turkey's rule is ever revisited. Postgres accepts it via SET TIME ZONE 'Europe/Istanbul'; or the timezone setting. Because the offset is currently fixed, a cron job's local-time schedule behaves identically every day of the year, with no DST boundary or skipped/duplicated hour to account for.

History and quirks

Turkey used the standard Eastern European Time / Eastern European Summer Time cycle (+02:00/+03:00) from 1927 until 2016, when the government announced clocks would stay on +03:00 (the summer offset) permanently rather than falling back that October — a decision initially framed as temporary but made permanent by decree in 2018. The declared motivations mixed energy policy with a desire for more evening daylight during the country's long working days, though the change proved contentious: darker winter mornings, especially in Turkey's western regions near Istanbul, sparked years of public debate about reversing it, echoing complaints raised in Russia's own permanent-DST period around the same time. Istanbul itself is a useful reminder that IANA time zone names describe legal jurisdiction, not physical geography — the city spans the Bosphorus, straddling Europe and Asia, but the whole country runs on one zone regardless of which side of the strait a given neighborhood sits on.

Turkey's 2016 decision put it out of sync with its EU neighbors along the same offset band: before the change, Turkey followed the identical EET/EEST cycle as Greece and Bulgaria, so the three matched year-round. Since 2016, Turkey and Greece only match during the EU's own summer-time months, when Greece rises to +03:00 alongside Turkey's permanent offset — and sit an hour apart for the other half of the year, once Greece falls back to +02:00 standard time while Turkey stays put. That's a subtle but real complication for any system scheduling meetings or transport timetables across the Turkey–Greece–Bulgaria border region, since the "always the same offset" relationship that held for decades no longer applies for roughly five months of the year.

Offsets and DST transitions on this page are computed from the IANA time zone database bundled with your browser; the rules described above were verified against tzdata 2026b when this page was published.