Ferry from Santorini (Athinios Port) to Ios.

Ferries from Santorini to Ios operate on 6 to 7 days a week all year. Journey: 35m to 1h 50m. Quick hop to the party island.

Ios is Santorini's closest big neighbour to the north, about 21 nautical miles away, and the two make a natural pair. Many travellers use Ios as the lively counterweight to the caldera: days on Mylopotas and the other long sandy beaches, nights in the bars of Chora, and a far more relaxed price level than Santorini. Outside July and August, Ios turns into a quiet, rugged island of chapels, hiking paths and empty coves.

The crossing is so short that the choice of boat matters mostly for price. A seat on the conventional ships can cost a fraction of the high-speed fare, and the time difference is only half an hour or so. The catamarans win if you want to leave later or arrive earlier in the day; the big ferries win on cost, space and open decks.

The part that takes planning is getting to Athinios, Santorini's main port and the one all Ios boats use, which sits at the bottom of the caldera cliffs and gets congested in summer. Book your transfer in advance and leave early. On Ios, by contrast, you step off right by the beach and a short ride from Chora. From there, onward boats to Naxos, Paros and Piraeus make it easy to continue north.

Weather can lengthen this crossing, especially in July and August when the meltemi blows from the north. The high-speed boats are the most affected and may be delayed or held in port if the coast guard judges the sea too rough, while the big conventional ships usually keep sailing. The operator will rebook or refund a cancelled ticket, and on a crossing this short, with several boats on most summer days, the easy fix is usually a later or larger ship the same day.