Choosing your week

The best month for a Santorini boat tour, honestly

7 min read

The best month for a Santorini boat tour is late May to mid-June, or the second half of September. September water sits at about 24 °C, warmer than June, and the meltemi has usually weakened by then. July and August give the warmest sea and the strongest wind of the year.

Every month between April and October works. They are not the same day out. The gaps are wider than most people expect: nearly two hours of sunset time and eight degrees of sea temperature between the extremes. In August the shared boat is full at fifteen. In October it often is not.

The table below is the whole answer. Everything under it is the reasoning.

The numbers

Month by month on the water

Sunset times are computed with the NOAA solar equations for 36.4167° N, 25.4333° E, at sea level, in Athens local time for 2026. Publish them as approximate: they shift by up to a minute across the leap cycle. Sea temperatures are the Climates to Travel monthly averages, and other publishers give figures within about a degree either way.

Month	Sunset, 1st and 15th	Typical wind	Sea °C	Crowds	Verdict
April	19:40 → 19:52	Settling. Mostly F3–5	16.5	Low	Sail yes, swim briefly. The most likely month to lose a day to wind.
May	20:05 → 20:17	Mostly settled. F3–5, occasionally F6	18.5	Low to mid	Rising fast. Late May is one of our two picks.
June	20:30 → 20:38	Meltemi establishes from mid-month	22.0	Mid to high	Longest days of the year and warm-enough water. The other pick, to mid-month.
July	20:40 → 20:37	Peak meltemi. F4–7, gusting F8	23.5	High	Warm water, hardest wind. Take the 10:00 departure, not the 15:00 one.
August	20:25 → 20:10	Peak meltemi. F4–7, gusting F8	24.5	Highest	Warmest sea of the year, roughest afternoons, fullest boats. Book earliest.
September	19:48 → 19:27	Meltemi weakens. Often F4 or less late in the month	24.0	Mid	The best all-round month here. Warmer water than June, calmer than July.
October	19:03 → 18:43	Southerlies return. F3–6, occasionally F7	22.0	Low	Quiet water and good value. Keep a spare day; late October is a gamble.

The latest sunset of the year falls around 1 July at 20:40. From there it comes back nearly two hours by mid-October. Clocks go back on 25 October 2026, so the last days of the month lose another hour on the clock overnight. Wind descriptions follow sailingissues.com and greeka.com, both seen 25 August 2026. The crowds column tracks published demand, not a headcount. The market season runs April to October, with June to September carrying the heaviest booking pressure. The Greek cruise levy at Santorini is set at €20 per passenger from June to September, against €12 in April, May and October.

The fact that decides it: September water is warmer than June water

Almost everyone assumes the sea gets colder as the summer ends. It does, but two months late.

Water holds heat far longer than air does. The Aegean spends all summer absorbing it and only starts giving it back in the autumn. So the sea peaks in August at about 24.5 °C and is still at 24 °C through September, while June — which feels like high summer on land — is a full two degrees cooler at 22 °C.

That single lag is why the second half of September is the month we would book. The water is at its best, the meltemi has usually stood down, the boats are no longer full, and sunset is still late enough for a 15:00 departure to make sense.

The same lag is what makes April difficult. The air is pleasant and the sea is 16.5 °C. You will sail happily and swim for about ninety seconds.

If you only care about one thing

Most people are optimising for one variable and pretending to weigh five. Find your row.

What matters most to you	Book	Why
Warm water for swimming	August, then September	24.5 °C and 24.0 °C. Nothing else comes close, and September is calmer.
The calmest possible sea	Late September, or May	The meltemi peaks mid-July to mid-August and weakens through September.
A late sunset on deck	Late June to mid-July	20:38 to 20:40. By 15 September it is 19:27, and by 15 October 18:43.
Fewest people, on the boat and off it	Late April, or October	Both sit outside the June to September demand peak. October also has warmer water.
The lowest chance of a weather cancellation	June, or early September	Settled enough to be reliable, without the July and August meltemi at full strength.
Not losing a day of a short holiday	Any month, booked early in your stay	The buffer matters more than the month. A cancellation on day two can be re-sailed on day four.
Price	Any month	Ours does not move with the season. €100 per person, all seven months.

The market does discount the shoulder months. Viator's 2026 listings for a shared five-hour catamaran day cruise run from about €60 at the bottom of the band to €150 at the top, with typical pricing around €100 to €110 (seen 25 August 2026). We publish one price and keep it.

Our two picks, and why they are narrow windows rather than months

Late May to mid-June. The wind has settled and the meltemi has not yet organised itself. Days are at their longest, so a 15:00 sunset departure still gets five useful hours. The sea reaches 22 °C by June, which is swimmable for most people without ceremony. The island is busy but not yet saturated.

The second half of September. Water at 24 °C. Afternoons that no longer blow F6. Sunset at 19:27 on the 15th, moving back roughly three minutes a day, so a fortnight changes your departure by twenty minutes. Fewer boats at every stop.

Both windows are about a fortnight long, which is why we do not simply say June or September. The first week of June is not the last week of June, and the first week of September is not the last.

What does not change with the month

The price. €100 per person on the semi-private day and sunset cruises, €1,200 for the whole boat with up to eight guests, in April and in August alike.

The boat and the numbers. Fifteen guests maximum on a shared cruise, and that number does not move. Five hours. Lunch cooked on board, wine, beer, water, snorkelling gear and towels, and a car from your hotel and back.

The captain's call. He decides on the morning whether the sea is safe, in June as in October. A weather cancellation is refunded in full or moved to another date, whichever you prefer.

What does move is the clock. Departure times shift through the season because the sun does. The time on your confirmation is the time that applies.

One thing we do not publish is our own first and last sailing dates of the year. The market season is April to October; ours has not been written down. Message us on https://wa.me/306989771888 for a date in early April or late October and you will get a straight answer.

Ready when you are

Send us the two weeks you are choosing between

Tell us the dates and what matters most — swimming, sunset, calm water, or having the stops to yourselves. We will tell you which week we would take, including when the answer is the cheaper one.

Check availability & book

Call the harbour office+30 698 977 1888

Common questions

What is the warmest month to swim in Santorini?

August, at about 24.5 °C, with September within half a degree of it at 24 °C. The sea lags the air by roughly two months, so late-season water is warmer than early-season water. June, which feels like high summer on land, is two degrees cooler than September.

When is the wind worst in Santorini?

Mid-July to mid-August, when the meltemi peaks. It is a persistent northerly that can blow at Force 5 to 6 and rise quickly to Force 7, occasionally Force 8. It builds through the day and eases in the early evening, so a morning departure is the more comfortable one.

Do Santorini boat tours operate in April and October?

Both months operate across the market, with more weather cancellations than midsummer. April water is cold at 16.5 °C; October is far warmer at 22 °C. Build a spare day into either month so a wind cancellation does not cost you the cruise entirely. Ask us before booking a date in early April.

Which month has the latest sunset in Santorini?

Early July. The latest sunsets of 2026 fall around 1 July at 20:40, with mid-June close behind at 20:38. By 1 September it is 19:48 and by 15 October 18:43. Clocks go back on 25 October, which takes another hour off the last days of the season.

When is the best month to sail?

Late May to mid-June, or the second half of September. Both give settled wind, warm-enough water and long-enough days. September is the stronger of the two on sea temperature; June is the stronger on daylight. July and August are perfectly good if you take a morning departure.

Is September better than June for a Santorini boat tour?

On the water, usually yes. The sea is 24 °C against June's 22 °C, and the meltemi is weakening rather than building. June wins on daylight, with sunset at 20:38 against September's 19:27, which matters if a long evening on deck is the point of the trip.

Santorini Boat Tour - Water Taxi is a catamaran cruise and water taxi operator based in Fira, Santorini.

Updated August 2026