Best time to visit Hanoi: weather, crowds and events by month

Hanoi has four seasons, unlike southern Vietnam. Winter is cool and often grey with a fine drizzle locals call mưa phùn; summer is hot, humid and broken by thunderstorms. The two shoulder seasons are the ones most travellers want.

Use the table to pick a window, then check the forecast in the last week: a late-September typhoon or an early cold snap can shift the picture by several degrees.

December to February: mornings around 12–15 °C, afternoons near 20 °C, and a damp cold that makes a light puffer or fleece worth carrying. Sa Pa and Ha Giang, if you add them, run several degrees colder and can approach 0 °C at night.

March and April warm up quickly: 21–29 °C, low rain, and the best odds of clear days for a Hạ Long or Ninh Bình side trip. Pollen and haze can bother sensitive travellers in March.

May to August is the hard stretch: 33–36 °C with high humidity, so plan indoor or shaded blocks at midday and expect a heavy afternoon shower. July and August are the storm peak — Hạ Long cruises can be cancelled on a warning, so keep a spare day.

September is a transition month: still warm, with typhoon risk that shifts toward the central coast later in the season. October and November are the payoff — 22–30 °C, lower rain, and the city at its most walkable.

Hanoi is a year-round city, so the swings are smaller than at a beach resort, but the holiday spikes are real. The Tết week (6 February 2027, lunar and moving yearly) empties many restaurants and shops for 3–7 days while filling trains, buses and flights a week either side. The 30 April–1 May long weekend and National Day on 2 September do the same for domestic travel.

October and November are the sweet spot: good weather, low-to-medium crowds, and hotel rates below the December peak. Late January to February outside Tết and June are the cheapest windows, but you pay in drizzle or heat.

Book transport and beds 3–6 weeks ahead for Tết and the April–May weekend; a week is usually enough in October and November.

Tết is the big one. The city is decorated, flower markets run for days before, and the streets are unusually quiet on the first two mornings — but many family-run restaurants and shops shut, and museums keep holiday hours. If you want the atmosphere without the closures, arrive 3–4 days before Tết and leave before the holiday week.

Mid-Autumn Festival (around 15 September 2027, lunar — check) is not a day off, but the Old Quarter fills with lanterns and toy stalls in the evening; it is a good reason to be in the city for one night.

National Day on 2 September brings closures of central streets for events and a domestic travel peak. Vietnam Culture Day, a paid public holiday added in 2026, falls on 24 November — offices and some museums may close; check the 2027 arrangement.

Hanoi is cheap by US and European standards, and the seasonal spread is modest: expect roughly 20–40% higher room rates around Christmas–New Year and Tết than in October or June. A mid-range double in the Old Quarter runs about 900,000–1,800,000 VND (about $35–70) in shoulder season, and 1,400,000–2,600,000 VND (about $55–100) at the December peak — 2026 estimates, check current rates.

Flights move more than hotels. Domestic seats around Tết and 30 April–1 May can double, and the Hanoi–Ho Chi Minh City route is the busiest in the country. Rain in July–August rarely costs you a hotel night, but a cancelled Hạ Long cruise can cost a prepaid tour, so read the operator's weather policy before booking.