Which time zone do Bangkok and Hanoi observe year-round?

Bangkok and Hanoi observe Indochina Time year-round. This time zone corresponds to UTC+07:00, meaning local clocks run seven hours ahead of Coordinated Universal Time.

Indochina Time is used across mainland Southeast Asia. Thailand, Vietnam, Cambodia, and Laos all keep this offset, although each country may use its own national name for the same clock time. Bangkok and Hanoi therefore share the same time despite being in different countries.

Neither Thailand nor Vietnam currently observes daylight saving time, so the offset does not change seasonally. That makes this a useful contrast with places where clocks move forward or backward during the year.

A common mix-up is Singapore or Malaysia, both of which use UTC+08:00—one hour ahead. The word “Indochina” refers to the mainland Southeast Asian region, not every country in Southeast Asia.