How many hours is UTC behind CHAST?
As abbreviations, CHAST is always 12.75 hours ahead of UTC: UTC is UTC+0 and CHAST is UTC+12:45. To convert, add 12.75 hours.
Check which label you actually need: CHAST (Chatham Time is on UTC+13:45 today). A time written with an abbreviation that is not in use is usually meant as the local time, so convert between the places instead: right now CHAST is 13.75 hours ahead of UTC.
When the UTC to CHAST time difference changes
For most of the year CHAST is 13.75 hours ahead of UTC. From 4 April to 25 September 2027, CHAST is 12.75 hours ahead of UTC instead, because the two places change their clocks on different dates. Meetings booked by the usual gap land an hour off in those weeks.
| Dates | CHAST vs UTC | Length |
|---|---|---|
| 27 September 2026 to 31 December 2026 | 13.75 hours ahead | 96 days |
| 1 January 2027 to 3 April 2027 | 13.75 hours ahead | 93 days |
| 4 April 2027 to 25 September 2027 | 12.75 hours ahead | 175 days |
| 26 September 2027 to 31 December 2027 | 13.75 hours ahead | 97 days |
Best time for a meeting between UTC and CHAST
- When CHAST is 13.75 hours ahead of UTC: no shared 09:00 to 17:00 hours; try 07:00 in UTC (20:45 in CHAST).
- When CHAST is 12.75 hours ahead of UTC: no shared 09:00 to 17:00 hours; try 07:00 in UTC (19:45 in CHAST).