Things to Do in Koh Samui in May
May weather, activities, events & insider tips
May Weather in Koh Samui
Is May Right for You?
Advantages
- Shoulder season pricing means 30-40% lower rates than December-March peak period - you'll find four-star beachfront resorts for ฿2,500-4,000 per night that cost ฿6,000+ in high season, and most tour operators offer early-booking discounts if you reserve 2-3 weeks ahead
- Beaches and popular sites are genuinely manageable - you can actually get photos at Chaweng Beach without crowds, snorkeling tours to nearby islands run with 15-20 people instead of 40, and restaurants don't require advance reservations except on weekends
- The sea conditions are actually excellent for water activities - May sits right before monsoon season starts in earnest, so you get calm, clear waters with 15-20 m (49-66 ft) visibility for snorkeling and diving, plus consistent enough conditions that boat tours rarely cancel
- Local fruit season is in full swing - mangosteen, rambutan, and durian are everywhere at markets for ฿40-80 per kilo, roughly half what you'd pay in winter months, and the morning markets in Lamai and Nathon are packed with seasonal produce that locals are actually buying for themselves
Considerations
- Rain is genuinely unpredictable - those 10 rainy days don't tell the full story because you'll also get brief 15-30 minute afternoon showers on supposedly dry days, usually between 2-5pm, which can disrupt beach plans if you're not flexible with timing
- The humidity at 70% combined with 32°C (90°F) temperatures creates that sticky, shirt-clinging feeling within minutes of being outside - it's the kind of heat that makes you want air conditioning breaks every few hours, not ideal if you're planning all-day outdoor adventures
- Some businesses operate on reduced schedules - a handful of beach clubs and smaller tour operators close for May-June maintenance before monsoon season, and you'll find restaurant hours can be shorter than advertised online, particularly mid-week in quieter areas like Maenam
Best Activities in May
Ang Thong Marine Park snorkeling and kayaking tours
May offers ideal conditions for this archipelago of 42 islands - the seas are calm before southwest monsoon arrives, visibility underwater is 15-20 m (49-66 ft), and the limestone cliffs and hidden lagoons are spectacular without the crowds you'd face in high season. The kayaking through rock formations is actually easier in May's calmer waters, and you'll spot more marine life because fewer boats are churning up the seabed. Tours typically depart 8am and return by 5pm, giving you the full day before afternoon weather potentially shifts.
Wat Plai Laem and Big Buddha temple cycling routes
The 70% humidity sounds rough, but early morning temple visits by bicycle from 6:30-9:30am are actually perfect - you'll catch the coolest part of the day before heat peaks, see monks receiving alms, and have these ornate Chinese-Thai temples largely to yourself. The 12 km (7.5 miles) coastal loop from Bophut through Plai Laem to Big Buddha is flat, well-paved, and takes 2-3 hours with photo stops. May means fewer tour buses clogging the Big Buddha parking area, so you can actually appreciate the 12 m (39 ft) golden statue without battling selfie crowds.
Fisherman's Village and Lamai night market food walks
May evenings from 6-10pm are when locals actually come out after the day's heat breaks - you'll find authentic Southern Thai dishes at Fisherman's Village Friday market and Lamai Sunday market that cater to island residents, not just tourists. The ฿40-80 street food plates include regional specialties like kanom jeen nam ya (fermented rice noodles with fish curry) and khanom krok (coconut pancakes) that are genuinely better here than in Bangkok. The shoulder season means you can navigate the stalls without being shoulder-to-shoulder, and vendors are more willing to explain dishes.
Namuang Waterfall jungle hiking and natural pool swimming
The May rainfall actually works in your favor here - waterfalls are flowing stronger than the dry months of February-April, making the 30 m (98 ft) and 80 m (262 ft) cascades genuinely impressive. The 2 km (1.2 miles) jungle trail to the upper falls takes 45-60 minutes and is moderately challenging with some steep sections, but the natural pools at the base are perfect for cooling off in that humid heat. You'll see fewer tourists because it requires actual hiking effort, and the surrounding rainforest is lush and green from recent rains.
Thai cooking classes with market visits
May is actually ideal for cooking classes because you're working in covered kitchens during the hottest part of the day, and the morning market visits from 8-9am showcase all that seasonal fruit and produce locals are buying. You'll learn 4-5 dishes over 3-4 hours, typically including curry paste from scratch, pad thai, and a curry. The classes are hands-on, not demonstration-style, and you eat everything you make. May's smaller tourist numbers mean class sizes are 6-10 people instead of 15-20, so you get more instructor attention.
Sunset viewpoint drives and coastal photography routes
The variable May weather actually creates spectacular sunset conditions - those afternoon clouds that roll in often break up by 6pm, creating dramatic orange-and-purple skies that photographers love. The 50 km (31 miles) coastal ring road has multiple viewpoints including Lad Koh, Khao Hua Jook, and the southern coastal overlooks that face west for optimal golden hour light from 6-7pm. May's medium crowds mean you can actually set up a tripod without people walking through your shots, and the post-rain air clarity makes for sharper landscape photos.
May Events & Festivals
Visakha Bucha Day
This major Buddhist holiday commemorating Buddha's birth, enlightenment, and death typically falls in May on the full moon of the sixth lunar month - in 2026 that's likely May 12th. Temples across the island hold evening candlelit processions called wian tian where locals walk clockwise around the main hall three times carrying flowers, incense, and candles. Wat Plai Laem and Big Buddha are particularly atmospheric with hundreds of participants. It's a genuinely spiritual experience if you participate respectfully, and alcohol sales are prohibited island-wide that day, so plan accordingly.