Pelni (www.pelni.co.id), the national shipping line, operates large boats on infrequent long-distance runs throughout Indonesia. For Bali, Pelni ships stop at the harbour in Benoa. Schedules and fares are found on the website. You can enquire and book at the Pelni ticket office in Tuban.
You can reach Java, just west of Bali, via the ferries that run between Gilimanuk in west Bali and Ketapang (Java), and then take a bus all the way to Jakarta.
Ferries travel between Labuhan Lombok on Lombok and Poto Tano on Sumbawa frequently throughout the day.
Public car ferries travel slowly between Padangbai and Lembar on Lombok. There are also fast boats from various ports in Bali to the Gilis and Lombok.