The least rainy months in Tanzania vary depending on the region. In general, the months of June to September are the driest months in most parts of the country, particularly in the northern and central regions.

In the northern and central regions of Tanzania, including the Serengeti, Ngorongoro Conservation Area, and Tarangire National Park, the dry season runs from June to September. During this time, there is very little rainfall, making it an ideal time for wildlife safaris.

In the southern and eastern coastal regions, the driest months are generally from June to August, which coincides with the southern hemisphere winter. During this time, the weather is cooler and drier, with lower humidity and less rainfall.

It's important to note that climate patterns can vary from year to year, and some regions may experience more or less rainfall than usual during any given month. It's always a good idea to check local weather forecasts and conditions before traveling to Tanzania