September sits at the intersection of still-summer conditions and the beginning of genuine seasonal relief — hot, sunny, warm sea, full business hours, but noticeably less crowded than August, and often at slightly lower prices.
Weather
Temperatures average 23–28°C, occasionally touching 30°C in early September. The sea stays warm from summer — typically 25–26°C — making it excellent for swimming. The meltemi wind, which peaks in July and August, usually eases through September, making boat trips and diving conditions more reliable.
The harvest
September is Santorini's wine harvest month — the specific window when grapes are picked and some wineries run harvest-season events. If wine is a priority, September is the most interesting time to visit a winery beyond just a standard tasting (see our wineries guide).
Compared to August
The contrast is real even in early September. Oia's sunset viewpoint is busy but not the August wall-of-people experience. Restaurant reservations become easier to get with a few days' notice. Prices on accommodation start to come down. The general pace shifts perceptibly toward something more enjoyable.
Our verdict
For most visitors weighing August versus September, September wins. Unless you specifically need school holiday dates, the September version of Santorini is a meaningfully better experience at a lower cost. See our full best time to visit guide for the complete seasonal picture.
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