When to go
December through March is the reliable window: dry, calm seas, water clear enough for snorkelling, daytime highs around 30C. November and April sit on either edge and are usually fine, with April turning hot, up to 35C. The rainy season runs roughly April to November, heaviest June through September, when boat trips to the southern islands get cancelled and visibility underwater collapses.
Month by month in Vietnam
Phu Quoc sits in Vietnam, so the country's broader seasonal pattern applies. There is no single good month for all of Vietnam. North (Hanoi, Sapa) is coolest and driest Oct-Apr; centre (Da Nang, Hoi An, Hue) has its wet/typhoon season roughly Sept-Jan and is best Feb-Aug; south (HCMC, Mekong, Phu Quoc) is dry Dec-Apr, hot and humid year-round.
Jan-FebNorth cold and often grey; centre still wet early Jan then clearing; south dry, warm, one of the best windows overall.
Mar-AprNorth warming up and drier; centre good and increasingly busy; south hot, dry, pre-monsoon, Phu Quoc excellent.
May-JunNorth hot and humid with early rains; centre generally dry and good for beaches; south rainy season begins, afternoon storms.
Jul-AugNorth humid, occasional storms; centre still in its dry window, popular for Hoi An and Da Nang beaches; south wet season in full swing.
Sep-OctNorth transitioning, can be pleasant; centre's typhoon and flood season starts, riskiest months for the coast; south rains tapering off.
Nov-DecNorth turning cold and dry; centre still typhoon-prone into early Dec, Hue/Hoi An flood risk highest; south entering its dry season, good conditions.
About the author
Labeeb Mirza runs paid acquisition for an online used-car marketplace, across Google Ads, Meta, Reddit, TikTok, StackAdapt, Bing, and CTV/YouTube.