The best time to visit 泰國

What a year in 泰國 looks like

Thailand counts a hot season, a wet season and a cool one, where cool means dry and less hot rather than cold — except in the northern hills. What catches people out is that the Andaman coast and the Gulf have different wet seasons, so the months that soak one side are often the good ones on the other. Choose the month together with the coast, not separately.

The year, in windows

• November to February — The best-weather season for almost the whole country: dry, clear, and cool enough at night in the north to want a jacket. It is also the busiest stretch and when coastal room rates peak, so book ahead if this is your window.
• March to May — Proper hot season: high daytime temperatures with humidity building towards the end. Rates come down from the peak while the sea is still calm and clear. Move outdoor plans to morning and evening. The north often has air-quality problems early in this window from open burning.
• May to October (Andaman coast) — Phuket and Krabi enter the monsoon. Rain tends to come in short heavy bursts, the sea gets rough and some island boats stop running. Room rates are the lowest of the year. If you travel now, keep an indoor fallback and do not stack boat days back to back.
• July to September (Gulf coast) — Samui and its neighbours run opposite to the Andaman: these months are usually sunny with a calm sea, while this coast's heavy rain arrives late in the year, roughly October to December. That is why people switch coasts rather than postpone a trip.

The weeks to aim for

For maximum certainty regardless of price, take November to February. For the balance of weather against cost, take late October or June and match the coast to the month — that second approach usually buys a better trip for the money with almost no loss in weather.

The weeks to avoid

Songkran in mid-April is a long national holiday when the whole country travels at once and domestic flights and coaches fill quickly. If the festival is the point, it is worth being there; if a quiet beach is the point, avoid that week.

What the season does to a data plan

Coverage in cities, on inhabited islands and along main roads holds all year. Heavy rain does not cut mobile signal, though it does affect boats and some roads. Where it genuinely thins is open water between islands and the mountain roads in the north — download those routes in advance.