Interior cabins The indoor cabins are not equipped with portholes, windows or balconies; usually, in addition to being without openings except the door to the corridor, they could be, on some fleets, even slightly smaller, but it is not always so.

An inside cabin on a ferry is a private sleeping compartment that is located in the interior of the ship's hull, meaning it has no windows, portholes, or views of the outside world. These are typically the most economical accommodation options for overnight crossings (such as those in the Baltic or Mediterranean seas). Despite the lack of a view, modern inside cabins in 2026 are quite comfortable, usually featuring two to four bunks, a small desk, a closet, and a private ensuite bathroom with a shower and toilet. They are ideal for travelers who prioritize sleep and privacy over a view, or for those who are prone to seasickness, as being in the center of the ship often results in feeling less motion. Because they are windowless, they are also completely dark, which many travelers find helpful for getting a deep, uninterrupted night's sleep while the vessel is in transit.