Currently, this route is only operated by Small Cyclades Lines.
Donoussa and Koufonisia are close with a distance of only 26.05 kilometres between them, that's about 16 miles or 14 nautical miles if you take a direct route.
You can travel as a foot passenger or with your vehicle on this route.There are normally sailings on three days per week: Monday, Wednesday and Saturday. The cheapest price for a one way crossing by foot in the summer is about 5.40 euros, and for a car with one person about 22 euros
Click Book Now and use the booking form to get the latest prices and see the real sailing dates for all ferries on the Donoussa - Koufonisia route.
I traveled last year with Small Cyclades Lines from Donoussa to Koufonisia the ports were very small but the staff helps us a lot to board and get out of the ferry without a problem and the port police give us directions were to wait i will be back there for sure.