Island
Greek islands in September
Written by Elena Philippou, who hosts Villa Olivia Clara above Platis Gialos.Updated August 2026
September gives you August's sea without August. The water holds at 24 °C against August's 25 °C, days run 26–28 °C, and one or two days in the whole month see rain. The meltemi that wrecks boat plans in July drops away after the middle of the month. Our own rate falls from €2,200 a night in high summer to €1,600 from the 11th.
We host on Sifnos from the middle of May to the end of September, so September is the month we watch closest. It is the one stretch where the water, the wind and the price all move the right way at once.
The month is not uniform. The first ten days still feel like summer and are priced like it. From the 11th the rate drops, the meltemi eases, and the island starts handing itself back to the people who live here. The last week is quiet enough that some kitchens have already stopped.
The short answers
- Which island?
- Sifnos, if you want to swim, eat well and not queue. It has no airport, which keeps the September crowd down and means you come through Athens and take the boat. Paros, Naxos and Milos have airports and take Greek domestic flights only, so you connect in Athens for those too.
- Is the sea still warm?
- Yes. 24 °C in September against 25 °C in August. October holds 22 °C, which is still swimmable, and the season here closes on the 30th of September.
- How busy is it?
- Platis Gialos thins out after the first week. The front rows on the sand are there at eleven in the morning by mid-month, which they are not in August.
- What about the wind?
- The meltemi blows from about mid-May to mid-September. Late September into October is one of the two calm stretches of the year, so plan the boat day for the second half of the month.
August, September, October, side by side
Three months, the same three measures. The sea lags the air by a few weeks, so September swims better than it looks, and May at the other end of the season does not.
| Month | Sea | Daytime | Rainy days |
|---|---|---|---|
| August | 25 °C | 29–31 °C | 0–1 |
| September | 24 °C | 26–28 °C | 1–2 |
| October | 22 °C | 22–23 °C | 3–6 |
Monthly averages consistent with HNMS-derived climate normals for the nearest Cyclades stations, Milos and Naxos, and satellite sea-surface records. Verified June 2026.
The one date to book around
The "Nikolaos Tselementes" Cycladic Gastronomy Festival runs three days on the square at Artemonas, the 17th to the 19th of September in 2026. Tselementes was the cook who wrote the book every Greek kitchen owned, and he was from here. It is the island's own festival, and it lands in the cheaper half of the month.
Two families in one house
September suits two families sharing better than August does, because the beach is not full and the house is not at peak. Ours sleeps 8 in 4 bedrooms with 4.5 bathrooms, so four and four works without anyone drawing the short straw. The pool is private. Platis Gialos is 700 m down the hill, seven to ten minutes on foot, and it holds one of the two Blue Flags on Sifnos for 2026. The other is Kamares. There is parking for 5 cars, which matters when two families arrive in two hires.
What we would tell you not to expect
The season here ends on the 30th of September. The island winds down before that. Tavernas run Easter to September, and the last week of the month is when some of them stop for the year, so if you want everything open, come in the first three weeks. October keeps 22 °C water. It loses the certainty that the kitchen you walked to last night is open tonight.
September questions
- Is September a good time to visit the Greek islands?
- For swimming and eating, it is the best month of the year. The sea is 24 °C, a degree off August's 25 °C, the days are 26–28 °C, and there are one or two rainy days. Crowds and prices both fall after the first week. The trade is that the season is ending, so the last week of the month sees some places close.
- Can you swim in the Greek islands in September?
- Yes, comfortably, all month. The sea reaches 24 °C in September and is still 22 °C through October. It is warmer in September than it is in June, which surprises people, because the water takes most of the summer to heat up.
- Which Greek island is best in September for two families?
- An island with a walkable beach and no airport queue. On Sifnos, Platis Gialos is sand, shallow at the near end, and holds a 2026 Blue Flag. A four-bedroom house sleeping eight takes two families of four, and September rates are the lowest of the season from the 11th.
- Is it windy in the Greek islands in September?
- Less than in July and August. The meltemi blows from about mid-May to mid-September, so the second half of the month is one of the two calm stretches of the year. Book the boat day then.
- Is late September too late for a Greek island holiday?
- Not for the water, which holds 24 °C to the end of the month. It is late for certainty. Our own season closes on the 30th, tavernas run Easter to September, and the final week is when the island starts shutting for the winter.
September dates at the house
The rate drops on the 11th and the last bookable night is the 30th. Ask Elena what is still open.
See September availability