Best Time to Visit Thailand: Weather, Seasons, Festivals and Month-by-Month Guide (2027)

Thailand is hot all year and changes more with the rain than with the temperature. In Bangkok the average high only moves between about 32°C and 36°C, but monthly rainfall swings from about 12 mm in December to more than 330 mm in September. The two coasts also get their heaviest rain at different times. Here is what each part of the year is like, using the long-term averages for Bangkok, plus the 2027 dates worth planning around.

When is the best time to visit Thailand?

For most first trips, November to February is the best time to visit Thailand. This is the cool, dry season. Bangkok gets little rain, the Andaman beaches are calm, and the north has fresh mornings. It is also high season, and January was the busiest month for foreign arrivals in 2025.

March to mid-May is the hot season. April is the hottest month in Bangkok, with an average high of 35.7°C. It is a good time for the Gulf islands and for Songkran, but it is hard work for long days of sightseeing.

Mid-May to mid-October is the rainy season. Prices drop and the crowds thin out. Rain often comes in short, heavy bursts rather than all day, so travel is still possible. Koh Samui and the Gulf islands are a good choice in these months.

What are the seasons in Thailand?

The Thai government divides the year into three seasons. Summer, the hot season, runs from mid-February to mid-May. The rainy season runs from mid-May to mid-October. Winter, the cool season, runs from mid-October to mid-February.

The cool season is only cool by Thai standards. Bangkok still averages highs of about 32°C to 33°C. The real difference is in the nights, the humidity and the rain. In the south, heavy rain can carry on until December.

What is the weather like in Thailand month by month?

These are the 1991–2020 averages for Bangkok, from the climate normals based on Thai Meteorological Department data. The north is cooler at night in winter, and the south has its own rain pattern, but central Thailand follows this shape.

The numbers hide the humidity. Even in the dry months, Bangkok feels hotter than the thermometer says. Plan outdoor sightseeing for the morning and late afternoon, and keep the middle of the day for shade, museums or a pool.

When is the best time for the beaches?

Thailand has two coasts with two different monsoons. On the Andaman coast, which includes Phuket and Krabi, the wet months are May to October, with the most rain in September. The sea can be rough in these months. The coast dries out and calms down from October to December, and the dry months that follow are the main beach season.

On the Gulf coast, which includes Koh Samui, the heaviest rain comes later, from October to December, with a peak in November. From January to September Koh Samui gets under 140 mm of rain a month. That makes July and August a better time for Samui than November.

If your dates are fixed, pick the coast to suit them. In summer, go to the Gulf. In winter, go to the Andaman Sea.

When is the best time to visit Chiang Mai and the north?

November to February is the best time for Chiang Mai and the north. The skies are clear, and the nights are cool. In Chiang Mai the average low in January is 15.7°C, so bring a warm layer.

From about December to April the north has a smoke and haze season, caused mostly by agricultural and forest fires. It is usually worst in March and April, when air quality in Chiang Mai can reach unhealthy levels and the mountain views disappear. If you are sensitive to air pollution, avoid the north in these months or check the air quality index before you go.

What festivals and holidays are on in Thailand in 2027?

Buddhist holidays follow the lunar calendar. Loy Krathong falls on the full moon of the twelfth Thai lunar month, so check the official dates before you book.

When is Thailand busiest and most expensive?

December to February is peak season. Hotel and transport prices are at their highest, especially in December and January in Phuket, Krabi and Koh Samui. In 2025 January was the busiest month, with about 3.7 million foreign arrivals. Thailand had about 33 million foreign visitors in total that year, down from about 35.6 million in 2024.

May to October is the low season. Prices drop, and the Andaman resorts are much quieter. September was the quietest month for foreign arrivals in 2025. These months are a good choice if you want lower prices and do not mind some rain.

What should you pack for Thailand?

Pack light, breathable clothes for heat and humidity, plus sunscreen, a hat and insect repellent in every season. Temples require covered shoulders and knees, so bring a light scarf or long trousers. In the rainy season add a small umbrella or a light rain jacket and sandals that can get wet. For the north between November and February, bring a fleece or jumper for the cool mornings and nights.

Facts checked October 2026. Climate figures are 1991–2020 averages for Bangkok, based on Thai Meteorological Department data. Buddhist holidays and Loy Krathong follow the lunar calendar, and festival dates are confirmed by the Thai authorities and organisers; check official sources before you book.