The best time for visiting most of Laos is between November and February, when it rains the least and is not too hot. It's also Laos's main season for both national and regional bun (festivals).

If you plan to focus on the mountainous northern provinces, the hot season (from March to May) and early rainy season (around June) is not bad either, as temperatures are moderate at higher elevations. Southern Laos, on the other hand, is best avoided from March to May, when day-time temperatures break into the 40s and nights aren't much cooler.

The rainy season is not as bad as you might think. While it will rain -very heavily - the downpours are often fairly brief and can be brack­eted by long periods of sunshine. The rains also clear dust from the skies and land, making everything clearer and brighter. Of course, there are downsides; unsealed roads can become quagmires and extensive travel in remote areas like Salavan, Phongsali and Sainyabuli might be impos­sible. River travel can be a good alternative during these months. If you intend to travel extensively by river, November is the best; flooding has usually subsided yet river levels are still high enough for maximum navi­gability. Between January and June, low water can make navigating some rivers difficult.

December to February and August are the peak tourist times. January, in particular, is very busy and booking ahead is advisable.