European Time Zone Abbreviations Explained

A Paris meeting invite that says "CET" in July is wrong by one hour. For seven months of the year, Central Europe runs on CEST, not CET. The same three letters also get confused with US Central Time, and "IST" can mean Dublin, Mumbai or Tel Aviv depending on who sent the calendar entry. Getting the abbreviation right matters before anyone dials in.

What do European time zone abbreviations mean?

The naming follows a consistent logic. A base label covers the colder months. For summer, most zones add an "S" (for "Summer") to that base. The majority of the continent shifts together, on the last Sunday of March and the last Sunday of October, at 01:00 UTC. That simultaneous switch means local clock time differs by zone: 01:00 in WET locations, 02:00 in CET locations, 03:00 in EET locations.

Winter designations: WET, CET, EET

Three base labels cover the continent from late October to late March.

• WET, Western European Time, UTC+0. Portugal (mainland and Madeira), Ireland, the United Kingdom, the Faroe Islands, and Spain's Canary Islands.
• CET, Central European Time, UTC+1. The zone used by the largest number of European nations, stretching from Spain to Poland and from Norway to Italy.
• EET, Eastern European Time, UTC+2. Finland, Estonia, Latvia, Lithuania, Ukraine, Romania, Bulgaria, Greece, Cyprus, and Moldova.

Summer designations: WEST, CEST, EEST

When clocks go forward, these replace the winter labels.

• WEST, Western European Summer Time, UTC+1. Same territories that use WET in winter.
• CEST, Central European Summer Time, UTC+2. Every CET nation adopts this during summer.
• EEST, Eastern European Summer Time, UTC+3. Every EET nation adopts this during summer.

Which European abbreviations stay fixed all year? GMT, MSK, TRT

Several European territories never move their clocks.

• GMT, Greenwich Mean Time, UTC+0. Iceland stays on GMT all year. The UK uses GMT in winter but switches to BST in summer. Colloquially, people say "GMT" when they mean UTC+0, but the distinction matters for a London call in August.
• MSK, Moscow Time, UTC+3. Russia runs on MSK year-round with no DST. The country spans multiple zones, but its European portion (Moscow, St Petersburg, Kaliningrad) sits at UTC+3.
• TRT, Turkey Time, UTC+3. Turkey dropped DST in 2016 and remains on UTC+3 permanently. Same offset as MSK and EEST, but the official label is TRT.

Abbreviation pitfalls: BST, IST, CET confusion

These three cause the most scheduling errors.

BST: British Summer Time vs Bangladesh Standard Time

BST is British Summer Time (UTC+1), the summer label for the United Kingdom, Guernsey, Jersey, and the Isle of Man. The same three letters also stand for Bangladesh Standard Time (UTC+6). A "10:00 BST" meeting invite means London in July or Dhaka. In a European context, BST always means British Summer Time.

IST: Irish Standard Time vs India Standard Time vs Israel Standard Time

IST is Irish Standard Time (UTC+1). Ireland uses IST as its summer designation. But IST also means India Standard Time (UTC+5:30) and Israel Standard Time (UTC+2). A 10:00 appointment in Dublin is 14:30 in Mumbai. Same three letters, four and a half hours apart.

CET confused with US Central Time

CET (Central European Time, UTC+1) is not the same as CT or CST (Central Time in the United States and Canada, UTC-6 in winter, UTC-5 in summer). The gap between CET and US Central Time is 6 or 7 hours depending on DST. Writing "CET" when you mean "Central Time" and assuming the reader will decode it is a fast way to miss a call.

EET confused with EAT

EET (Eastern European Time, UTC+2) is sometimes mixed up with EAT (East Africa Time, UTC+3). The difference is one hour. Read a flight arrival listed in EAT as EET and you will be at the gate an hour late.

What are the less common European time zone abbreviations? AZOT, FET

• AZOT, Azores Time, UTC-1. The Azores (Portugal) are the only European territory west of UTC+0. In summer they switch to AZOST (Azores Summer Time, UTC+0).
• FET, Further-eastern European Time, UTC+3. This label is less standardised. It occasionally appears for Belarus, western Russia, and Turkey. In practice, Belarus uses UTC+3 year-round, Russia uses MSK, and Turkey uses TRT. Official schedules rarely show FET.

Which European time zone abbreviations should I use for each country?

Further reading: CET vs CEST: What’s the Difference?, European Time Zones Map 2026, IANA Time Zones in Europe: A Developer’s Guide.