The Maldives sits close to the equator and is warm year-round — temperatures stay between 24°C and 33°C in every month. The real variable is rain and sea conditions.
November to April is the dry season and the best weather window. Skies are clear, seas calm, visibility underwater is at its best, and there's little rain. January to April are the driest months of all. This is also peak season: resorts fill up and prices spike sharply, particularly over Christmas and New Year when rates can double or triple. Book well ahead if you're travelling then.
May to October is the wet season, driven by the southwest monsoon. Rain is more frequent, seas rougher, and wind picks up — but the rain typically falls in short, intense bursts rather than all-day grey drizzle, and many days are still perfectly fine. Resorts offer significant discounts (sometimes 30–50% off rack rates), and the crowds thin out. If budget matters, shoulder season — May and October in particular — can offer genuinely good conditions at reduced prices.
Diving considerations. The two seasons bring different conditions to different atolls. The eastern atolls (including North and South Malé) are generally better in the dry season; the western atolls (including Ari Atoll) can be better in the wet season when currents bring nutrients in from the west. Whale sharks are present in Ari Atoll year-round, but manta ray aggregations in Baa Atoll's Hanifaru Bay peak between June and November — deep in the wet season. If mantas are your priority, wet season it is.
Surfers head for the Maldives between March and October, when the southern swells produce the breaks that the country's surf camps are built around.