Koh Samui
May 1, 2023

Koh Samui in May: What to expect

May on Samui gets an average of 215 hours of sun. That’s almost 7 hours a day – sound good? I think so.

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Koh Samui in May

Whether you’ve planned it to perfection or you’re just lucky, May is a gorgeous time to visit Koh Samui – and there’s lots to look forward to besides sunshine. As for the climate, May is still Koh Samui’s “hot” season. Given Samui’s location just a few degrees above the equator, that’s saying something. How to ensure you don’t melt? Read on for packing tips and hotel recommendations that will help you in the heat.

Koh Samui in May: Weather, Events and What to Expect
A May sunset on Koh Samui

Is May a good time to visit Koh Samui?

May on Samui gets an average of 215 hours of sun. That’s almost 7 hours a day – sound good? I think so. As well, May is pretty quiet compared to mid-to-late June and July/August when families arrive for holidays with school-aged children.

Two pieces of certain science: (1) Children in the UK, Australia, the States and Canada (and much of the rest of the world) are in school in May. (2) You can always find peace and quiet somewhere on Koh Samui, no matter the month.

Where to stay in May

Koh Samui in May: Weather, Events and What to Expect
SALA Samui Chaweng

My pick: SALA Samui Chaweng

I think this resort stands out as a superb spot for couples and why not enjoy it best when you've practically got the island to yourself? Choose between rooms or pool villas on the ocean side or the garden side of the resort. (The latter offers a little more shade). If planning to spend all day, every day, at the beachfront pool – double up on sunscreen, and don't forget cover-ups. It's absolutely beautiful but gets v-e-r-y strong sun (reflecting off white buildings) from sunrise all day.

More hotel ideas

Tip: For an introduction to Koh Samui’s beaches and great hotel suggestions, see Where to Stay on Koh Samui.

What to pack for May

What to pack for Koh Samui in May
Clockwise: Reef-friendly sunscreen, Fodor's Thailand 2022, packable day pack, deodorant travel wipes

1. Sun protection

Given the long days and promise of gorgeous sunshine in May, make sure you bring cover-ups for the sun and quality sunscreen that will last when you’re in and around water. I particularly recommend a water-resistant, reef-friendly sunscreen with a high SPF. A giant sun hat (this one is rollable/foldable/packable) is crucial if you burn easily (or, y'know, don't want wrinkles). Finally,  a UPF rash guard or swim top is ideal to wear when snorkelling or kayaking.

2. Thailand Guide

Fodor's Thailand travel guide is ideal for planning a wider Thailand itinerary (it covers Cambodia and Laos briefly too). I like Fodor's for its great range of itinerary suggestions and general interest/culture content. Within, find details on Thai history and a great FAQ on how to eat street food (“What are all the condiments for?”).

3. Adventure easily

May is a great time of year to try a huge variety of adventures and excursions on Samui. So, in addition to the things on my recommended Thailand packing list, it’s worthwhile to bring a day-trip bag that you can keep stocked with essentials (recap: sunscreen, sunscreen and more sunscreen). This backpack folds down to the size of a water bottle so it’s easy to have on hand when you need it.

4. Instant fix

Remember how we discussed that May is in Koh Samui's hot season? Keep these in your bag and I promise you'll be grateful to find them when you reach Peak Melt, miles away from a shower.

Tip: Take a quick look at Thailand’s location in relation to the equator – the Thai sunshine can do serious damage to your skin in minutes flat. Don't miss my sun safety tips (all recommended sunscreen is cruelty-free and I've tested it myself in Thai heat and humidity).

May events calendar

Koh Samui in May: Weather, Events and What to Expect

Thai Mother's Day isn't until August, but if you're celebrating, find some suggestions for finding flowers and breakfast in bed for your favourite mama bear.

Weather in May

Koh Samui in May: Weather, Events and What to Expect
May on Chaweng Beach

May averages

  • Temperature: 30°C / 86°F
  • Sunshine (hours/day): 6
  • Rainy days: 9 days (160mm / 6 inches)
  • Sea temperature: 28°C / 82°F

What’s the weather like on Koh Samui in May?

Expect temperatures anywhere between 28-35 degrees Celsius (that’s 82-95 Fahrenheit) – perhaps with the occasional shower. Don't panic about the possibility of rain. Samui's tropical storms are amazing – and they don't last long at this time of year. The Koh Samui Guide is fully stocked with rainy day ideas, including a full checklist of activities to keep you perfectly entertained in any weather. (Note that Phuket gets twice as many rainy days in May – 18, on average).

Your questions

Koh Samui in May: Weather, Events and What to Expect
Frangipani (aka plumeria) flowers blooming in May

Is May or June better on Koh Samui?

Refer to everyone’s favourite Thai-glish phrase: “Same same”. Your daylight hours will be 11 minutes longer in early June versus early May. As for the weather? Can you tell the difference between 1°C? On average, rainfall is very slightly heavier in May but over the same amount of time (so, if it rains, it’s just more emphatic in May than in June). Both are great times to visit Koh Samui.

  • Temperature (avg): 30°C in May vs 29°C in June
  • Sunshine (hours): 6 in May vs 6 in June
  • Rainy days (avg): 9 days (160mm) in May vs 9 days (100mm) in June
  • Sea temperature: 28°C in May vs 28°C in June

What’s the chance of rain on Koh Samui in May?

Minimal. Worst case – it rains a little bit across an average of 9 days in 31. Storms are usually pretty quick in May – rarely does the "rain/thunder" icon on your weather forecast mean that it rains all day, as in somewhere like the UK. Koh Samui weather does have seasonal variation, but May is (typically) still the hot, dry season.

Is May a good time to get married on Koh Samui?

Yes. Although you’ll need to make sure your guests are prepared for the considerable heat.

Is Koh Samui or Phuket better in May?

  • Temperature (avg): 30°C on Koh Samui vs 29°C in Phuket
  • Sunshine (hours): 6 on Koh Samui vs 8 in Phuket
  • Rainy days (avg): 9 days (160mm) on Koh Samui vs 18 days (200mm) in Phuket
  • Sea temperature: 28°C on Koh Samui vs 30°C in Phuket

Behind the scenes

Koh Samui in May: Weather, Events and What to Expect
Choeng Mon Beach in May

Hello and thank you to new customers this month in Australia, Belgium, Czech Republic, France, Germany, Hong Kong, Ireland, Israel, Netherlands, Norway, Poland, Singapore, South Africa, Spain, Sweden, Switzerland, Thailand, United Kingdom and the United States. My most exciting moment was my first ever customer in South Dakota ... meaning The Koh Samui Guide – finally – has customers in all fifty U.S. states.

Koh Samui in May

Koh Samui in May: Weather, Events and What to Expect
A throwback: May 2010 on Koh Samui

What’s next? To make sure you enjoy it all in full, you’ll need The Koh Samui Guide. You might wind up more excited, but definitely better prepared. Enjoy!

P.S. You can find every tip for Thailand packing and prep in the archive, or subscribe by email and get all the details straight to your inbox. Enjoy!

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