# When is the best time to visit Thailand? > Best time to visit Thailand: November to February for Bangkok and Chiang Mai, December to March for Phuket and Krabi, February to August for Samui. Month by month. - Source: https://clevertourists.com/resources/best-time-to-visit-thailand - Authors: Evan & Clara, Clever Tourists (first-hand, from years of travel across 20 countries) - Published: 2026-08-03 **The best time to visit Thailand is November to February**: Bangkok and the north are dry and at their least hot, and the Andaman coast (Phuket, Krabi, Ao Nang) has its calmest seas from December to March. The trade-off is that this is also peak season, with the highest room rates and the busiest beaches around Christmas and New Year. The one big exception is the Gulf coast (Koh Samui, Koh Phangan, Koh Tao), whose wettest months are October to December, exactly when the rest of the country is at its best. We spent six weeks in Thailand from 7 December 2022 to 21 January 2023, running Bangkok, Ayutthaya, Sukhothai, Lampang, Chiang Mai, Chiang Rai and Mae Hong Son, then south to Khao Sok and Ao Nang, so the route below follows the cool season. Temperatures and rainfall here are typical averages from long-term climate normals, not the weather of any one trip. ## Quick answer by priority • **Best weather overall:** December and January. Bangkok averages about 32 to 33°C (90 to 91°F) by day with almost no rain, and Chiang Mai drops to about 15 to 16°C (59 to 61°F) at night. • **Best for Andaman beaches (Phuket, Krabi, Ao Nang, Koh Lanta, Phi Phi):** December to March, when monthly rain stays under about 80 mm. • **Best for the Gulf islands (Samui, Phangan, Tao):** February to August. Avoid October to December. • **Fewest crowds with acceptable weather:** early November and the second half of February into early March, outside the Christmas and Chinese New Year peaks. • **Cheapest:** May to October, the southwest monsoon. Rain usually comes as heavy afternoon bursts rather than all-day grey, except on the Andaman coast in September and October. • **Festivals:** Songkran on 13 to 15 April 2027, and Loy Krathong with Chiang Mai's Yi Peng lanterns around the November full moon. • **Avoid:** the north from about February to April if you are sensitive to smoke, and Bangkok in April if you struggle with heat (average highs around 36°C / 97°F). ## Thailand month by month Figures below are typical averages for Bangkok unless stated, from long-term climate normals. Individual years vary. • **November:** about 25 to 33°C (77 to 91°F), rain falling off to about 50 mm. The rains end in the centre and north, crowds build late in the month. Good for Chiang Mai and Loy Krathong; bad for Koh Samui, which is in its wettest month (around 445 mm). • **December and January:** about 23 to 33°C (73 to 91°F), almost dry in Bangkok and Chiang Mai. Chiang Mai nights are about 15 to 16°C (59 to 61°F), so bring a layer for Doi Inthanon or Mae Hong Son. Peak prices from about 20 December to early January. This is when our route ran from Bangkok up through Sukhothai, Lampang and Chiang Mai. • **February:** about 25 to 34°C (77 to 93°F), still dry. One of the best months for the Andaman and the first good month for the Gulf. The north starts to get hazy. • **March and April:** the hot season. Bangkok averages about 35 to 36°C (95 to 97°F) by day, Chiang Mai about 35 to 37°C (95 to 99°F). Beaches still work, especially in March. April is Songkran month. • **May and June:** the southwest monsoon arrives. Bangkok gets about 250 mm in May; Phuket about 265 to 295 mm in May and June. Prices drop, the countryside turns green, and the Similan Islands close (16 May to 14 October in the 2026 to 2027 season cycle). • **July and August:** about 26 to 34°C (79 to 93°F) in Bangkok with roughly 175 to 220 mm a month. A good window for Koh Samui and Koh Tao, which get only about 100 to 115 mm. European summer holidays push island prices up again. • **September and October:** the wettest stretch for Bangkok (about 290 to 335 mm) and the Andaman coast (about 315 to 325 mm). Rough seas cancel some boat trips from Phuket and Krabi. The cheapest weeks of the year; flooding in low-lying areas is possible in some years. ## By region: three different rain calendars **Bangkok and the central plains (Ayutthaya, Lop Buri, Sukhothai):** dry from November to April, wet from May to October, with September the peak. Ayutthaya and Sukhothai are mostly open-air ruins with little shade, so the heat of March to May matters more than the rain. See our [Sukhothai Historical Park guide](https://clevertourists.com/resources/sukhothai-historical-park-tickets-bicycle-guide) and [day trips from Bangkok](https://clevertourists.com/resources/day-trips-from-bangkok). **The north (Chiang Mai, Chiang Rai, Lampang, Mae Hong Son, Pai):** the most pronounced cool season in Thailand, with only about 10 to 20 mm of rain a month from November to February. The catch is the burning season, roughly February to April, when crop and forest fires can push air quality to unhealthy levels. Read our [Chiang Mai burning season guide](https://clevertourists.com/resources/chiang-mai-burning-season-2027-haze-travel-guide) before booking March. Our stops at Chiang Mai (22 to 28 December) and Chiang Rai (28 December to 4 January) sat in the middle of the dry, clear stretch. More in [where to stay in Chiang Mai](https://clevertourists.com/resources/where-to-stay-in-chiang-mai) and [how many days in Chiang Mai](https://clevertourists.com/resources/how-many-days-in-chiang-mai). **Andaman coast (Phuket, Krabi, Ao Nang, Khao Sok, Koh Lanta, Phi Phi):** the southwest monsoon hits this coast directly, so May to October is wet and seas are rough, while December to March is the clear, calm window. Khao Sok's rainforest and Cheow Lan Lake are easier in the dry months too; we went on from Khao Sok to Ao Nang in mid-January. **Gulf coast (Koh Samui, Koh Phangan, Koh Tao):** the pattern is shifted. Summer is relatively dry, and the heaviest rain falls in October to December when the northeast monsoon arrives. If you can only travel in July or August, this is where to put your beach days. ## Festivals, holidays and closures in 2027 • **Chinese New Year, 6 February 2027:** busy in Bangkok's Yaowarat (Chinatown) and in hotels across the country, as visitors arrive from China and the rest of the region. • **Songkran, 13 to 15 April 2027 (Tuesday to Thursday):** the Thai New Year water festival. Chiang Mai's water fights around the old city moat usually run longer than the official days. Buses and trains out of Bangkok fill up before it. See our [Songkran 2027 guide](https://clevertourists.com/resources/songkran-2027-chiang-mai-bangkok-water-festival-guide). • **Similan and Surin Islands:** closed each year from mid-May to mid-October; the current cycle reopened on 15 October 2026 and runs to 15 May 2027. • **Loy Krathong and Yi Peng, about 14 November 2027:** set by the full moon of the 12th Thai lunar month, so treat it as provisional until Chiang Mai publishes its programme. Our [Yi Peng and Loy Krathong guide](https://clevertourists.com/resources/yi-peng-loy-krathong-2026-chiang-mai-dates-lantern-guide) has the details. ## Prices and crowds Room rates peak from about 20 December to the first week of January, then again around Chinese New Year. In those weeks the islands and Chiang Mai's old city book out first. February is still high season but noticeably calmer after Chinese New Year week. The best value is the shoulder: **early November** (rains have ended in Bangkok and the north, beach prices not yet at peak) and **late March to April** for the Andaman coast if you can handle the heat. On the Gulf islands, **July and August** combine good weather with lower prices than December, although European families push rates up then. Domestic trains and buses are the first thing to sell out around Songkran and New Year. If you plan to ride the night train north, read our [Bangkok to Chiang Mai sleeper train guide](https://clevertourists.com/resources/bangkok-to-chiang-mai-sleeper-train-first-vs-second-class-guide). ## When not to go, honestly **Andaman coast in September and October:** this is the real low point. Rain averages over 300 mm a month in Phuket, red flags close beaches to swimming, and island-hopping boats from Krabi and Phuket get cancelled. Go to the Gulf instead. **Koh Samui in November:** the wettest month there, with around 445 mm on average. Many people book Samui for a December honeymoon and get the tail of this. **Chiang Mai in March and April:** hot, with a real risk of smoke haze. If you have a respiratory condition, choose November to January for the north. **The rainy season elsewhere is not a write-off.** In Bangkok and the north, June to August usually means a heavy afternoon storm and dry mornings. Temples, markets and food work fine, and you pay low-season prices. For the full six-week route we used, see our [Thailand itinerary](https://clevertourists.com/resources/thailand-itinerary-our-6-week-route-bangkok-north-to-the-andaman) or the shorter [2-week Thailand itinerary](https://clevertourists.com/resources/thailand-itinerary-2-weeks), and our [Thailand guide](https://clevertourists.com/guides/thailand). ## Frequently asked questions ### What is the cheapest month to visit Thailand? May to October is the low season, and September and October are usually the cheapest weeks. They are also the wettest months in Bangkok and on the Andaman coast, so put beach time on the Gulf islands instead. ### What is the rainy season in Thailand? For Bangkok, the north and the Andaman coast it runs roughly May to October, peaking in September. The Gulf islands (Koh Samui, Koh Phangan, Koh Tao) are different: their wettest months are October to December. ### Is December a good time to visit Thailand? Yes for Bangkok, the north and the Andaman coast: it is dry, Chiang Mai nights are about 15 to 16°C, and seas around Phuket and Krabi are calm. It is peak season, so book late December early, and avoid Koh Samui, which is still wet. ### When should I avoid Chiang Mai? Roughly February to April is the burning season, when smoke from crop and forest fires can push air quality to unhealthy levels. November to January is the best window for the north. ### What is the best time to visit Thailand for beaches? December to March for Phuket, Krabi and Ao Nang; February to August for Koh Samui, Koh Phangan and Koh Tao.