There is KTEL service from Athens to Vathi all year round, via Patra and Sami.
The bus embarks on the ferry boat. The trip's total duration is 8 hours 30 min.
By F/B:
From Patra:
From Athens There is daily KTEL service to Patra. From Patra, There is service to Vathi in Ithaki, via Sami, Kefalonia (5 hours), all year round.
From Astakos, Aetoloakarnania:
There is daily KTEL service from Athens to Astakos in Aetoloakarnania. The distance is 297 km (5.5 hours). From Astakos There is service to Vathi in Ithaki, all year round. The distance is 23 n.m.