Asia/Ho_Chi_Minh

TZ identifier and aliases

Asia/Ho_Chi_Minh is the canonical identifier for Vietnamese civil time, covering the entire country. Asia/Saigon is an older name still pointing at the same rules — retained from the city's name before reunification — but is a deprecated alias; use Asia/Ho_Chi_Minh in new code.

UTC offset and DST rule

Asia/Ho_Chi_Minh is +07:00 year-round with no daylight saving time. Vietnam briefly experimented with DST once, decades ago, but has kept a single fixed offset for the entire country since — there's no seasonal clock change to account for in any system built against this zone.

Using it in cron, CI and Postgres

Set TZ=Asia/Ho_Chi_Minh for a process that should schedule by Vietnamese local time. Postgres accepts it via SET TIME ZONE 'Asia/Ho_Chi_Minh'; or the timezone setting. Because the offset never changes, a cron job's local-time schedule behaves identically every day of the year, with no DST boundary or skipped/duplicated hour to plan around.

History and quirks

The tz database identifier itself is a small piece of Vietnamese political history: the city was named Saigon until 1976, when it was renamed Ho Chi Minh City following reunification under the Socialist Republic of Vietnam, and the IANA database's naming convention — which generally prefers a country's largest city or historical administrative center as the zone's label — was updated to match, leaving the older Asia/Saigon identifier in place only as a backward-compatible alias. Vietnam spans a long, narrow north-south strip of territory but a comparatively narrow east-west one, so unlike wide countries such as Indonesia or Russia, a single national time zone has never created the kind of severe sunrise/sunset mismatch that motivates zone splits elsewhere. Vietnam has tried daylight saving only once, briefly, and the practice never returned, leaving Asia/Ho_Chi_Minh one of the more historically stable zones in this batch alongside its regional neighbors Thailand and Cambodia.

Before reunification, Vietnam had briefly been split across two different civil administrations with separate time zone policy during the war era, though both North and South Vietnam ultimately used the same +07:00 offset in practice, so the 1976 tz database update was mainly a naming change reflecting the new capital-adjacent city name rather than an actual shift in the underlying offset. Ho Chi Minh City's continued growth as Vietnam's largest metropolitan area and primary economic hub — larger than the capital, Hanoi, which also sits within this same Asia/Ho_Chi_Minh zone — is part of why the tz database's convention of naming a country's zone after its most prominent city, rather than its political capital, produced this particular identifier.

Offsets and DST transitions on this page are computed from the IANA time zone database bundled with your browser; the rules described above were verified against tzdata 2026b when this page was published.