Time zone · Oceania

CIST

Cook Islands Standard Time

Cook Islands Standard Time (CIST) keeps things simple at a steady UTC-10:00, with no daylight saving changes and a single zone across the islands — life in the Cook Islands feels effortlessly sync’ed to one timeless rhythm, perfect for seamless global calls and relaxed scheduling.

UTC-10:00 standard1 IANA zone1 city
Current time in CIST☀ Daylight
17:29:50

Saturday, May 30, 2026

07:0812:3618:04
Standard
-10 · −10
IANA zones
1

Current offset

UTC-10:00

Standard · -10

Daylight saving

Not observed

Year-round standard time

IANA zones

1

None observe daylight saving

DST offset

—

No summer variant

About CIST

A fixed, year-round offset.

Cook Islands Standard Time (CIST) keeps things simple at a steady UTC-10:00, with no daylight saving changes and a single zone across the islands — life in the Cook Islands feels effortlessly sync’ed to one timeless rhythm, perfect for seamless global calls and relaxed scheduling.

IANA zones · the technical identifiers

The zone that resolve to CIST.

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.

IANA zonePrimary cityDST
Pacific/RarotongaRarotonga— None

Cities currently on CIST

The same hour, city by city.

1 city · all UTC-10:00

Avarua
17:29
17:29:51 · -10
 CIST year-round

Where CIST is used

One country.

Cook Islands
CIST · UTC-10:00

Same offset · UTC-10:00

Other zones at UTC-10:00 right now.

These named zones share CIST's offset today. When daylight saving rules differ, they drift apart for part of the year.

HSTUTC−10
--:--
Hawaii-Aleutian Standard Time
Americas▲ Observes DST
United States
TAHITIUTC−10
--:--
Tahiti Time
Oceania— No DST
French Polynesia

Frequently asked questions

Common questions about CIST, daylight saving, and how to handle it in software. Can't find what you need? Email [email protected].

Does Rarotonga observe daylight saving time?
No, Rarotonga does not observe daylight saving time, maintaining a consistent UTC-10:00 year-round.
Which countries use Cook Islands Standard Time?
The Cook Islands are the sole nation using CIST, with Rarotonga as its representative zone.
When did the current offset become valid?
The UTC-10:00 offset has been in effect since May 30, 2021.
What is the UTC offset for Cook Islands?
CIST is fixed at UTC-10:00 without seasonal changes.

Free · Developer API

Time, as JSON.

Every IANA time zone with live offsets, DST status, and the countries and cities that use them — clean, dependable JSON. Sign up free and get an API key in seconds.

GET /v1/timezones Live

countries, cities, convert, DST transitions coming next.

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// France's time zones, right now
GET /v1/timezones?country=fr
{
"data": [
{
"iana": "Europe/Paris",
"display_name": "Paris",
"current": {
"utc_offset": "+02:00",
"abbreviation": "CEST",
"is_dst": true
}
}
]
}