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Jet lag plan

Hanoi → Phnom Penh

Hanoi and Phnom Penh share the same time zone.

About 1,058 km due south · approximately 2.2-hour non-stop flight · a medium-haul flight.

On arrival

  • Hanoi and Phnom Penh are in the same time zone — no jet lag adjustment needed.

About the Hanoi → Phnom Penh route

The route from Hanoi, Vietnam to Phnom Penh, Cambodia covers roughly 1,058 kilometres in a due south direction. At standard jet cruise speed plus a one-hour allowance for taxi, climb, and descent, a non-stop flight takes about 2.2 hours. Both cities sit in the northern hemisphere, so the seasonal direction of daylight (longer days in June, shorter in December) matches between origin and destination.

Hanoi is in the tropics, so day length varies only slightly across the year. Light cues for the circadian system stay strong year-round. Phnom Penh is in the tropics, so day length varies only slightly across the year. Light cues for the circadian system stay strong year-round.

Business-hours overlap

Standard 09:00–18:00 working hours at both ends of this route overlap by approximately 9 hours. In Hanoi that window runs 09:00 to 18:00; in Phnom Penh it is 09:00 to 18:00. This is the realistic window for live meetings, customer calls, or pair work without forcing either end out of normal hours.

Daylight saving on this route

Neither city observes daylight saving time, so the hour offset on this route is fixed year-round. This makes recurring schedules and calendar invites with collaborators on the other end safer than for DST-observing pairs.

Frequently asked questions

How long is the flight from Hanoi to Phnom Penh?

The great-circle distance from Hanoi to Phnom Penh is about 1,058 kilometres. A typical non-stop flight takes around 2.2 hours at standard cruise speed; routes with connections add two to four hours.

What is the time difference between Hanoi and Phnom Penh?

Hanoi and Phnom Penh share the same time zone, so there is no clock offset on this route.

Is jet lag worse flying east or west on this route?

No circadian shift is required between these two cities.

Should I take melatonin for the Hanoi → Phnom Penh trip?

For a shift of 0 hours, melatonin offers little benefit beyond what consistent light exposure already provides. The Cochrane review on jet-lag melatonin shows the strongest effects on shifts of five hours or more.

Do I need a pre-trip schedule shift for Hanoi → Phnom Penh?

For a shift under two hours, pre-trip adjustment is usually not worth the effort.

What chronotype handles this route best?

Chronotype does not affect adjustment on a same-time-zone route.

Sources

Popular routes from Hanoi

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