Sunset Time in Koh Samui Today

Sunset & Daylight Patterns Specific to Koh Samui

Koh Samui sits at 9.5° N in the equatorial zone. It is the wetter half of the year there now, and the sun currently spends 12 hours above the horizon each day.

Sunsets are latest in June around the summer solstice and earliest in December. Near the solstices, the sunset time barely shifts day to day; near the equinoxes (March, September), it moves up to 2 minutes per day. Day length barely moves in Koh Samui: 12.7 hours at the longest and 11.6 at the shortest, a swing of well under two hours. Planning here is about rain and cloud timing, not about racing the light.

Golden hour in Koh Samui lasts about 41 minutes today, with civil twilight adding a further 21 minutes of usable blue-hour light after sunset.

The most photogenic sunset conditions in Koh Samui come in February, March, April, when the atmosphere is clearest and high-pressure systems push cloud layers away from the western horizon. Koh Samui has the opposite weather pattern to Phuket — when the Andaman coast is stormy in May-October, Samui stays largely dry, making it Thailand's best monsoon-season escape.

Civil twilight at Koh Samui's latitude lasts approximately 21 minutes after the sun drops below the horizon — this is the "blue hour" window of soft, diffused light that photographers prize above all others. At 9.5°, this window is brief, making precise timing critical — the sky transitions from golden to dark in under half an hour.

Sun & Moon Times in Koh Samui

Sunset timing in Koh Samui is driven by latitude and season. We apply atmospheric refraction corrections for accuracy within one minute. Golden hour begins roughly 60 minutes before sunset — the most valuable window for photography, outdoor dining, and evening walks.

Sunset in Koh Samui shifts by several minutes each week. Summer evenings are longest, winter sunsets arrive earliest. Cloud cover near the horizon does not change the sunset time itself, though it can hide the sun a few minutes early and often produces the most dramatic color displays.

For the best sunset experience, arrive at your viewing spot 30 minutes before the listed time. Conditions can shift — check again on the day itself.

What Determines Sunset Time?

Sunset time in Koh Samui is determined by the city's latitude, longitude, and the time of year. During summer, the Earth's axial tilt causes the sun to take a longer path across the sky, resulting in later sunsets. In winter, the opposite occurs — shorter days mean earlier sunsets. Near the equinoxes (March and September), sunset times change most rapidly, shifting by 2–3 minutes per day. At Koh Samui's latitude, the difference between the earliest and latest sunset can be several hours across the year. Our daily calculations use precise astronomical data to give you the exact sunset time accurate to the minute.