Ferry from Ios to Thirasia

The ferry route from Ios to Thirasia is a small but interesting Cycladic crossing that usually operates seasonally, mainly in the summer months, and is typically scheduled only a few times per week rather than every day. At the moment, several booking engines report no active sailings on the Ios to Thirasia route, or show it as “seasonal with no current departures,” which suggests that services can be irregular and may not run every year, so travellers need to double check live availability close to their travel dates. When it operates, the route is normally served by small conventional or high speed ferries, often connected with regional lines in the southern Cyclades, and the sailing time is generally quoted at about 1 hour to 1.5 hours for the roughly 32 kilometre distance between the 2 islands. Departures are from the main port of Ios (Gialos) and arrive at the small port of Thirasia (usually Riva), where you can connect by road or boat to tiny villages and quiet beaches that feel a world away from nearby Santorini. Because this is a niche route with limited frequency, it is not usually suitable for a tight day trip and is better planned as part of a longer island hopping itinerary that includes other nearby islands such as Santorini, Sikinos or Milos.

Key information for the Ios to Thirasia ferry route

Ferry duration

The distance between Ios and Thirasia is about 32 kilometres, and sources that describe connections from Thirasia to Ios mention a typical ferry time of around 1.5 hours depending on the vessel and intermediate stops. Some guides refer to this as a relatively short regional crossing, but you should always confirm the exact duration on your chosen date because timings can change with route adjustments and different ships.

Ferry companies

In recent seasons, information sites list Seajets as an operator that has served the Ios to Thirasia ferry route as part of its Cyclades network, although schedules are not guaranteed every year. Blue Star Ferries and other major companies focus on the busier Piraeus to Ios and Santorini to Ios routes, so any direct Ios to Thirasia connection is usually a niche seasonal line rather than a large, daily service.

Fast vs slow ferry

When the Ios to Thirasia ferry route is active, it may be operated by either a smaller high speed vessel or a conventional ferry, and this will affect the crossing time. However, because the distance is modest and the service is infrequent, most travellers choose primarily based on schedule and availability rather than the slight time savings between a fast and a slow ship.

Best time to travel

The Ios to Thirasia ferry route is typically available seasonally from June to September, which means summer is the main window if you want a direct connection between these 2 islands. Within that period, July and August bring the warmest weather and busiest ferries, while June and September often offer a balance of milder crowds and more comfortable temperatures, but still require careful checking of the timetable because frequency can be low.

Sea conditions and wind

The waters between Ios and Thirasia lie in the same Meltemi affected area as Santorini and the central Cyclades, so strong north winds in July and August can make the sea choppy and may lead to timetable disruptions. Travellers sometimes report that windier days can feel rough on smaller high speed ferries, so if you are sensitive to motion it is sensible to choose morning departures when possible and to avoid very windy days if you have flexibility.

Port guide

On Ios, ferries to Thirasia depart from the main port at Gialos, a busy harbour with cafés, ticket offices and bus connections up to Ios Town and to the main beaches, which makes it straightforward to reach even if you stay away from the waterfront. On Thirasia, ferries generally arrive at Riva port, a tiny harbour with limited services, so you should not expect big facilities, and you may need to pre arrange accommodation or onward transport to small villages such as Manolas.

Car rental advice

Some ferries that link Ios with Thirasia may accept vehicles, especially if they are part of a longer Cycladic route, but because this is not a high frequency line you must check both the vessel type and your rental agreement before planning to take a car. Given that Thirasia is a very small and quiet island, many visitors travel as foot passengers and then explore on foot, by local transport or with small boats, which can be simpler than dealing with vehicle reservations on a route that might not run daily.

Foot passenger tips

For the Ios to Thirasia ferry route it is sensible to arrive at Ios port at least 45 minutes before departure, particularly in high season, because services are limited and you will not want to miss the sailing. As a foot passenger, keep your ticket and identification easily accessible, and prepare a day bag with water, sun protection and any medication, since facilities at Riva on Thirasia are minimal compared with larger islands.

Is this route worth it?

The Ios to Thirasia ferry route is worth considering if you are building a slower, more off the beaten track Cyclades itinerary and want to combine the nightlife and beaches of Ios with the quiet, traditional atmosphere of Thirasia without transiting via busy Santorini. However, because current data shows no active sailings and previous years already had limited frequency, many travellers will find it more practical to sail from Ios to Santorini and then take a short local boat from Santorini to Thirasia instead.

Alternative route if cancelled

If your Ios to Thirasia ferry is cancelled or you cannot find any sailing on your dates, the most realistic alternative is to travel from Ios to Santorini and then use one of the regular Santorini to Thirasia connections, either from Athinios, Ammoudi or the old port of Fira depending on whether you travel on a local ferry or a day trip boat. This combination adds a leg to your journey but benefits from the high frequency Santorini to Ios ferries and the multiple daily options between Santorini and Thirasia in the main season.

Reverse route internal links

Booking platforms note that there is also a Thirasia to Ios ferry route defined in their systems, but they currently show no active departures, which mirrors the situation in the Ios to Thirasia direction. For your website, it will still be useful to create a “Ferry from Thirasia to Ios” page that explains the same seasonal and alternative route considerations in reverse and links to your more detailed Ios and Santorini ferry guides.