Greenland time zone history
Greenland has 4 zones of its own in the tz database. Standard times run from UTC−4 (Pituffik (Thule)) to UTC+0 (Danmarkshavn), a spread of 4 hours. Three of the 4 zones still change clocks for summer time under the current rules; the other 1 do not. The Ittoqqortoormiit zone has changed standard time most often since 1970: twice.
The 4 zones of Greenland since 1970
Zones at a glance
| Zone | Area covered | Standard time | Clock changes today | New standard times since 1970 |
|---|---|---|---|---|
| Danmarkshavn | National Park, east coast | UTC+0 | no, last in 1995 | 1 |
| Ittoqqortoormiit | Scoresbysund/Ittoqqortoormiit | UTC−2 | yes | 2 |
| Nuuk | Greenland (most areas) | UTC−2 | yes | 1 |
| Pituffik (Thule) | Thule/Pituffik | UTC−4 | yes | 0 |
What sets each zone apart
- Danmarkshavn: The largest single move came on January 1, 1996, when clocks went forward 3 hours, from UTC−3 to UTC+0. On standard time, clocks at Danmarkshavn run 1 hour 15 minutes ahead of local mean solar time, the largest gap of the 11 zones on UTC+0 standard time whose clocks run ahead of the sun.
- Ittoqqortoormiit: On standard time, clocks at Ittoqqortoormiit run 32 minutes behind local mean solar time, the fifth-largest gap of the 79 zones whose clocks run behind the sun. On March 31, 2024 the summer offset, UTC−1, became permanent standard time; the clocks did not move that day.
- Nuuk: The latest change of standard time came on March 25, 2023, from UTC−3 to UTC−2.
- Pituffik (Thule): Seasonal clock changes began only in 1991 and are still in use. Pituffik (Thule) kept local mean time (UTC−4:35:08) until 1916, the latest switch of the 19 zones on UTC−4 standard time.
How the zones compare with Nuuk since 1970
- Danmarkshavn: same time as Nuuk except 11,323 days in 1996–2026; 2 hours ahead today.
- Ittoqqortoormiit: usually 2 hours ahead of Nuuk; different on 5,265 days in 1970–1981 and 2023–2026; same time today.
- Pituffik (Thule): usually 1 hour behind Nuuk; different on 3,685 days in 1980–2026; 2 hours behind today.
Every change of standard time since 1970
4 changes across the 4 zones, oldest first.
- March 29, 1981 Ittoqqortoormiit: UTC−2 to UTC−1
- January 1, 1996 Danmarkshavn: UTC−3 to UTC+0
- March 25, 2023 Nuuk: UTC−3 to UTC−2
- March 31, 2024 Ittoqqortoormiit: summer offset kept as standard time
Clock changes in 2026, 2027 and 2028
March 8, 2026 (forward 1 hour); November 1, 2026 (back 1 hour); March 14, 2027 (forward 1 hour); November 7, 2027 (back 1 hour); March 12, 2028 (forward 1 hour); November 5, 2028 (back 1 hour)
March 28, 2026 (forward 1 hour); October 25, 2026 (back 1 hour); March 27, 2027 (forward 1 hour); October 31, 2027 (back 1 hour); March 25, 2028 (forward 1 hour); October 29, 2028 (back 1 hour)