Great Circle Distance between Heathrow and Samui Airport is 6,148 miles, with a flight time of approx 12.5 hrs. Koh Samui's IATA airport code is USM.
Show Samui Airport on map.
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Climate:
In Ko Samui, the climate is tropical, hot all year round, with a long rainy season due to the monsoon of Southeast Asia, which runs from May to mid-January, and a drier season from mid-January to April. The driest months are February and March, when, however, some showers can sometimes occur. The temperature is high throughout the year, around 30°C during the day and 25°C at night. The coolest months are December and January, while from February to May, an increase in temperature is observed, though less marked than in the mainland of Thailand; April and May are, albeit slightly, the hottest months. In the summer months, the heat continues to be intense and sultry, though tempered by sea breezes. The amount of sunshine is good in the driest period, from mid-January to April, while in the rest of the year, the sun often shines, but it alternates with some cloudiness, more or less widespread, and associated with rain showers.
Routing Options
| Route 1 | LGW‑BKK
(BA)  | BKK‑USM
(PG)  |
|
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 2 | LHR‑BKK
(TG)  | BKK‑USM
(PG) |
|
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 3 | LHR‑HKG
(BA) | HKG‑USM
(CX)  |
|
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 4 | LHR‑SIN
(BA) | SIN‑USM
(PG) |
|
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 5 | LGW‑BKK
(BA) | BKK‑HKG
(CX) | HKG‑USM
(CX) |
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 6 | LHR‑BKK
(TG) | BKK‑HKG
(CX) | HKG‑USM
(CX) |
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 7 | LHR‑DOH
(QR)  | DOH‑BKK
(QR) | BKK‑USM
(PG) |
| TOTAL
(SGL) | TOTAL
(RTN) |
|---|
| Route 8 | LHR‑DOH
(QR) | DOH‑BKK
(QR) | BKK‑HKG
(CX) | HKG‑USM
(CX) | TOTAL
(SGL) | TOTAL
(RTN) |
|---|
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