Typically, the Galápagos Islands have two distinct seasons – cool and dry between June and November, and wet and warmer between December and June. The warm season tends to be the best time to visit, as the sea is calmer and you'll enjoy better underwater visibility during those diving and snorkelling trips.
Wildlife is present on the Galápagos all year-round, but what species you'd like to see will dictate the month you visit. In June, you'll have a good chance of spotting humpback whales, while May is when the rare blue-footed boobies perform their courtship dances. In December, the hatching season begins for Giant Tortoises.