Kos to Piraeus is one of the longer hauls in the Greek network, running the length of the Aegean from the eastern Dodecanese down to Athens' main port. It's less a quick hop than a proper sea voyage, and most people who book it are either avoiding a flight connection or building the crossing itself into the trip -- a cabin and a night on deck watching the islands slide past, or a full day spent reading in the lounge as the ferry works its way through the Cyclades. Check the schedule box above for the latest confirmed dates before you plan around it.
Service runs daily for as long as the season is published, though on this route "daily" usually means a single sailing rather than a shuttle -- the crossing is long enough that operators don't stack multiple departures in a day. In the busiest weeks of summer a second, faster boat sometimes joins the roster, but don't count on it; treat one sailing a day as the baseline and check the box above for what's actually confirmed on your dates.
Useful Resources for Your Greek Island Trip
- Find accommodation in Greece – hotels, apartments and villas on Booking.com
- Book tours and activities in Greece via Viator
- Find guided experiences and day trips via GetYourGuide
- Compare car hire prices in Greece via DiscoverCars
Exploring Athens?
If you have time before or after your ferry, there is plenty to see near the capital. Browse our complete guide to the best day trips from Athens – from ancient ruins and mountain villages to coastal escapes and island hops.