Verdict: Excellent month
Koh Samui Weather in March
March runs warm in Koh Samui, with daily highs around 28°C (82°F) and nights near 23°C (73°F). Expect showers on roughly 11 days of the month — rarely trip-ruining, worth planning around. Overall, March is one of the best months of the year to be in Koh Samui.
Average high
28°C / 82°F
Average low
23°C / 73°F
Rain days
~11
Precipitation
37 mm
What to pack for Koh Samui in March
- Summer clothes, plus one light layer for air-con and evenings
- High-SPF sunscreen, sunglasses, and a refillable water bottle
- A packable rain shell or compact umbrella earns its space
- Comfortable walking shoes — every guide on this site assumes you'll use them
March against the rest of the year
Warmest in Koh Samui: Apr (29°C / 84°F) · Coolest: Dec (25°C / 77°F) · Wettest: Oct (~27 rain days)
26°
22°
Jan
26°
22°
Feb
28°
23°
Mar
29°
24°
Apr
29°
24°
May
29°
24°
Jun
28°
23°
Jul
29°
23°
Aug
27°
23°
Sep
26°
22°
Oct
26°
22°
Nov
25°
22°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)