The Ionians are reached differently from the Aegean islands: there is no ferry from Piraeus. You fly in, or you cross from the western mainland ports. Each island’s main connection runs to the coast rather than to a single island hub, which means Corfu and Kefalonia - at the north and the middle of the chain - are not one hop apart the way Paros and Naxos are.
What our island pages actually describe
Corfu anchors the group’s north. Its sea route is the mainland one, from Igoumenitsa, and it runs year-round.
Kefalonia links onward in season. Fiskardo, on its northern tip, links north to Lefkada in season, and the loop keeps going from there. Kefalonia also connects to Zakynthos in summer, from Pesada to Agios Nikolaos, roughly mid-June to late September.
So the chain exists, and in high season it is genuinely walkable island to island. What we cannot tell you from our own sources is whether a single direct Corfu-to-Kefalonia sailing is running in the season you are travelling. Check the current timetable with the operators rather than assuming either way - that is the honest position, and it is why this page does not print a crossing.
The three realistic shapes
Overland down the west coast. The most reliable version in any season: cross from Corfu to Igoumenitsa, then drive south. It is a long day, and it is the one that does not depend on a seasonal link.
Island to island through Lefkada. The pretty version, and a trip in itself rather than a transfer. Lefkada is the one you can drive onto, which makes the southern half of this chain easier than the northern half.
Fly via Athens. The fallback when the season is wrong, and the same shape as the Corfu-to-Santorini problem: no direct connection, so you go through Athens and lose most of a day.
Should you do it at all
Worth asking. Corfu and Kefalonia are the two biggest arguments in the Ionian and they are genuinely different islands - Corfu greener and more urban with a Venetian old town, Kefalonia larger, more mountainous and the one you drive.
Corfu vs Kefalonia settles which one suits your trip, and the honest answer for a single week is usually one of them, properly, rather than both with a travel day in the middle. For two weeks, the chain becomes worth it.
Our Corfu guide, our Kefalonia guide and the Ionian islands map the group.