According to the route plan recently announced by Hellenic Seaways, this year it will connect Santorini with Piraeus, Rafina and Heraklion.
More specifically, from the spring of 2018, the routes of Santorini are the following:
PIRAEUS-SIFNOS-IOS-SANTORINI with the Hellenic HighSpeed
From 30 / 3 to 30 / 9
- From Monday to Sunday, departure from Piraeus at 07:05 and arriving in Santorini at 12:35.
- Return every day leaving Santorini at 13:15 pm and arriving in Piraeus at 18:45 pm
RAFINA-MYKONOS-NAXOS-IOS-SANTORINI with the Flyingcat 4
From 30 / 3 to 17 / 4 and from 25 / 5 to 30 / 9
- From Monday to Sunday, departure from Rafina at 07:15 and arriving in Santorini at 12:00
- Return every day leaving Santorini at 12:15 and arriving in Rafina at 16:55
HERAKLION-SANTORINI-IOS-PAROS-MYKONOS with Highspeed 7
From 5 / 4 to 15 / 10
- From Monday to Sunday, leaving Heraklion at 09:00 and arriving in Santorini at 10:45
- Return every day departing from Santorini at 17:25 pm and arriving in Heraklion at 18:50 pm