Covers Phuket, Koh Samui, Koh Lanta, Koh Phi Phi, Bali, Palawan, the Maldives, Mauritius, the Seychelles and Zanzibar, with visa and park rules checked at the source.
UpdatedThis page carries dated prices, schedules or seasonal facts checked on the date above, and that window has now passed. Re-check the sources at the foot of the page before you book.
January is the easiest month to pick a Thai island. The Andaman coast, home to Phuket, Koh Lanta and Koh Phi Phi, is in its dry season, with flat water on the west-facing beaches and boat trips running on schedule. Phuket's January data shows 87°F (30°C) highs, a sea at 84°F (29°C) and 2.9 inches (73 mm) of rain for the month.
The one island that slips is Koh Samui, on the Gulf of Thailand. January is the tail of its rainy season, so it ranks last this month even though it wins from spring to fall. The cards below give the order; the sections explain the two coasts and the January costs.
Score = 55% this month's weather + 45% the island's other five factors. How we score
| # | Island | Score | High °F | Sea °F | Rain (in) |
|---|---|---|---|---|---|
| 1 | Phuket | 8.3 | 87 | 84 | 2.9 |
| 2 | Koh Lanta | 7.8 | 88 | 84 | 3.5 |
| 3 | Koh Phi Phi | 7.6 | 87 | 84 | 2.9 |
| 4 | Koh Samui | 7.5 | 82 | 83 | 5.3 |
1Phuket wins January on both halves of the score. Its January weather score is 9.5, with 87°F highs, an 84°F sea and 2.9 inches of rain, and it has the strongest year-round scores of the four: 8.5 for things to do and 10 for value. A well-reviewed 4-star in Patong was $76 for January 13, 2027. The catch is people: January is high season on Thailand's busiest island. Base yourself at Kata or Karon for calmer nights.
2Lanta is second on a 9.2 January weather score: 88°F highs, an 84°F sea and 3.5 inches of rain in its Krabi data. Its long beaches are at their calmest now, which suits young children at Klong Dao and Long Beach. It trails Phuket on things to do (5.5) and loses 0.4 points for being a dry-season island. The cheapest well-reviewed 4-star was $84 on January 13, 2027, and 3-star rooms started at $28.
3Phi Phi shares Phuket's January weather, a 9.5 with 87°F highs and an 84°F sea, but ranks third because it has less to do and costs more. The cheapest well-reviewed 4-star on Phi Phi Don was $187 for January 13, 2027, against $76 in Patong. January is a good month for Maya Bay, open since October 1, at $12 (400 baht) per foreign adult. Stay one or two nights to see the bays before the day boats arrive.
4Samui ranks last in January because it sits on the Gulf coast, where the rainy season runs late. Its January weather score is 8.4, with 5.3 inches of rain, 82°F highs and an 83°F sea, all a step behind the Andaman side. It is still pleasant, and a well-reviewed Chaweng 4-star cost $84. Pick Samui in January only for its pool villas; from March to October it moves to the top.
In this guide
Each island's January score blends two things: 55% is its January weather score (daytime high, sea temperature, rainfall, sunshine and any storm season) and 45% is everything else we score year-round, which is beaches, things to do, access, value and crowds, with 0.4 points off for islands our pages rate as worth it only for some travelers. The method is set out in how we score islands.
Our weather data is read at each island's gateway airport. Phi Phi has no airport, so it shares Phuket's January numbers; Lanta's come from Krabi.
Thailand's islands sit on two seas with opposite rainy seasons. The Andaman coast (Phuket, Phi Phi, Lanta) gets the southwest monsoon from about mid-May, with its heaviest rain in September. By January that is long gone. The Gulf coast (Samui) gets the northeast monsoon instead, heaviest from mid-October to early December, and the Thai Meteorological Department puts the southern east coast's rainfall peak at November to January.
That is why Samui's January weather score is 8.4 against 9.5 for Phuket. Samui still has a decent month; it simply has more showers, 5.3 inches (134 mm), and a cooler 82°F (28°C) afternoon. The coasts swap places in spring: from March to October Samui ranks first. See our February and April pages for the crossover.
January is also high season, so the scenery is shared. Phuket counted 13.0 million overnight tourists in 2025, the busiest island of the four by a wide margin.
Cheapest well-reviewed hotel rated 4 stars or better on Kayak for Wednesday, January 13, 2027, taxes and fees in, checked October 20, 2026:
| Island (area) | January 13, 2027 | July 14, 2027, for comparison |
|---|---|---|
| Phuket (Patong) | $76 | $32 |
| Koh Lanta (west coast) | $84 | $52 |
| Koh Samui (Chaweng) | $84 | $58 |
| Koh Phi Phi (Tonsai) | $187 | $86 |
If a clean 3-star double is enough, Lanta's cheapest was $28 for the same night. Add $12 (400 baht) per foreign adult for Maya Bay if your Phi Phi tour does not include it.
No US airport flies nonstop to any Thai island. Fly to Phuket (HKT) through Bangkok, Singapore, Doha, Dubai, Istanbul, Seoul, Hong Kong or Taipei. For Lanta, fly to Krabi and continue about 24 miles (38 km) by road and car ferry. Phi Phi is 1 to 2 hours by boat from Phuket's Rassada Pier.
Since September 15, 2026, US citizens get a 30-day visa-free stay, down from 60, with up to 30 more days available by application in Thailand. File the free Thailand Digital Arrival Card within 72 hours before you land. Our passport rules guide has the details, and the world January ranking shows how Thailand compares with the Caribbean and Hawaii.
Lunch and snorkel gear are included; the national park fee is only included if you pick that option. Expect a crowded, fast day; Maya Bay closes for August and September.
Rating as shown on GetYourGuide
Pickup, guide, kayak and lunch are included; calm water, good for beginners.
Rating as shown on GetYourGuide
Price is per boat, so it suits a group; the park fee (400 THB per adult) and lunch are not included.
Rating as shown on GetYourGuide
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Yes, especially on the Andaman coast. Phuket, Koh Lanta and Phi Phi are in their dry season, with Phuket's January data showing 87°F highs and 2.9 inches of rain. Koh Samui on the Gulf coast is wetter.
It is fine but not the best. January is the end of the Gulf coast's rainy stretch, and Samui gets 5.3 inches of rain in our data against 2.9 for Phuket, with cooler afternoons around 82°F. Samui is at its best from February to September.
Koh Lanta. It ranks second this month, the sea is usually calm in the dry season, and Klong Dao and Long Beach slope gently. Phuket's Kata and Karon are the alternative if you want more to do.
Yes. Maya Bay closes every year from August 1 to September 30 and reopened on October 1, 2026. Foreign adults pay $12 (400 baht), and it can close for a day in rough weather.
In our dataset, January highs average 87°F (30°C) and the sea 84°F (29°C), with about 2.9 inches (73 mm) of rain over the month.
Further reading
