Time zone · Oceania
CHADT
Chatham Daylight Time
Chatham Daylight Time (CHADT) is the UTC+13:45 offset New Zealand’s Chatham Islands use during daylight saving (UTC+12:45 the rest of the year)—one of the few time zones worldwide with a 45-minute increment. While clocks may feel familiar to mainland New Zealanders, local schedules and connections shift when daylight saving ends, so global collaborators should double-check timing between late September and early April.
Thursday, October 15, 2026
Current offset
UTC+13:45
Daylight · +1345
Daylight saving
Active
Reverts 4 Apr 2027
IANA zones
1
1 observe DST, 0 don't
DST offset
—
No summer variant
About CHADT
Standard time, with a summer shift.
Chatham Daylight Time (CHADT) is the UTC+13:45 offset New Zealand’s Chatham Islands use during daylight saving (UTC+12:45 the rest of the year)—one of the few time zones worldwide with a 45-minute increment. While clocks may feel familiar to mainland New Zealanders, local schedules and connections shift when daylight saving ends, so global collaborators should double-check timing between late September and early April.
IANA zones · the technical identifiers
The zone that resolve to CHADT.
For software, always store the IANA identifier — never the abbreviation alone. The database keeps these zones distinct because their rules can, and historically did, diverge.
Where CHADT is used
One country.
Convert
CHADT to the world's clocks.
Frequently asked questions
Common questions about CHADT, daylight saving, and how to handle it in software. Can't find what you need? Email [email protected].
- Why does Chatham use a 45‑minute offset instead of a full hour?
- The Chatham Islands lie about 800 km east of mainland New Zealand, where the sun rises earlier, and their clocks are set 45 minutes ahead of the mainland’s. That gives a standard offset of UTC+12:45, one of the rare offsets that is not a whole or half hour.
- Is CHADT used anywhere besides the Chatham Islands?
- No. CHADT is used only in New Zealand’s Chatham Islands. No other regions or countries legally observe this exact offset.
- When does CHADT switch to/from standard time?
- Daylight saving starts on the last Sunday in September at 02:45 local time, when clocks jump forward to 03:45 (UTC+12:45 to UTC+13:45). It ends on the first Sunday in April at 03:45, when clocks go back to 02:45 (UTC+13:45 to UTC+12:45).
- How should I schedule meetings with someone on Chatham Island?
- Always confirm the date with your contact or use a trustworthy world clock. Rules are simple but easy to miss: from April to September they’re on UTC+12:45; for the rest of the year they shift to UTC+13:45.
- What happens during the ‘gap’ around the time change?
- When clocks go back in April, the hour from 02:45 to 03:45 happens twice; when they go forward in September, the hour from 02:45 to 03:45 is skipped. Some digital systems skip or duplicate events, so critical tasks like flights or deadlines are usually anchored to UTC.
- Does CHADT follow mainland New Zealand’s daylight saving rules?
- Conceptually yes—same spring-forward, fall-back pattern—but with a 45-minute twist. Instead of shifting between UTC+12 and +13, CHADT switches between +12:45 and +13:45.
- Do devices automatically update for CHADT?
- Most modern devices handle it correctly via time zone database updates, but older systems or custom calendars may still show the wrong offset. Manually verify annually if precision matters.
Source: IANA tzdb2026d · Reviewed
Free · Developer API
This time zone, as JSON.
Its defining offset, DST status and member counts, from one endpoint.
Also in the API: time zones by coordinates, conversions that flag daylight saving gaps, and abbreviations decoded.
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