One of the first questions travellers ask me is, “When should we go?” The honest answer is that Vietnam is so long — over 1,600 kilometres from top to bottom — that there is no single best month for the whole country. The trick is to match your dates to the regions you most want to see. Here is how I think about it.
The north — October to April
Hanoi, Ha Long Bay and the mountains around Sapa are loveliest in the cooler, drier months from October through April. Skies are clearer for cruising Ha Long, and the rice terraces of Sapa are at their most photogenic. December and January can be genuinely chilly in the far north, so pack a warm layer if you are trekking.
The centre — February to August
Hue, Hoi An and Da Nang follow a different rhythm. Their driest, sunniest stretch runs from February to August, which is also perfect beach weather along the central coast. The flip side is the wetter months later in the year, when Hoi An occasionally sees flooding — something to keep in mind if your heart is set on the lantern-lit old town.
The south — pleasant year-round
Ho Chi Minh City (Saigon), the Mekong Delta and the islands like Phu Quoc are warm all year. There is a wetter season from roughly May to October, but the rain usually comes in short, refreshing afternoon bursts rather than all-day downpours — easy to plan around.
Putting it together
If you want to combine north and centre in one trip, the shoulder months of March, April and September are my quiet favourites — you get agreeable weather across most of the country and fewer crowds than the peak. Tell me which places are top of your list and roughly when you can travel, and I will help you build the route around the best possible weather.