- S.A. Vaal (1961)
- Saaristo (1911)
- Saga Fjord (1957)
- Saga Lejon (1969)
- Sagafjord (1957)
- Saimatar (1899)
- Salerno Jet (1992)
- Saltsjöbaden 3 (1894)
- San Basilio (1876)
- San Frangisk (1990)
- San Pawl (1990)
- Sanct Svithun (1950)
- Sandhamn (2004)
- Sandnes (1950)
- Sandra D (1922)
- Santa Rosa (1958)
- Satu (2000)
- Savonlinna (1904)
- Saxaren (1999)
- Schilksee (1986)
- Schleswig-Holstein (1958)
- Schwentine (2007)
- Seagas (1974)
- Seeadler (1905)
- Seeadler (1964)
- Seeadler I (1964)
- Seemöwe II (1969)
- Segesta Jet (1999)
- Seine Princess (2002)
- Sekstant (1970)
- Selene (2002)
- Selinunte Jet (1999)
- Shelikof AVP 52 (1944)
- Shi Ji Kuai Hang (2002)
- Siletta Ace (1981)
- Silja II (1906)
- Siluna Ace (2008)
- Silver Star (1966)
- Silver Swan (1983)
- Silverfjord (1980)
- Silvertärnan (1986)
- Simara Ace (2007)
- Sinivuokko (1966)
- Sirena (1960)
- Sjögull (1982)
- Sjøkurs (1956)
- Sjøkurs (1950)
- Sjövägen (2014)
- HMS Skagul (1960)
- Skarven (1981)
- Skärgården (1978)
- Slite (1955)
- SNAV Antares (1990)
- SNAV Aquila (1992)
- Sochi-1 (1996)
- Sochi-2 (1996)
- Sofia (1974)
- Sofia (2020)
- Solent Express (2007)
- Sonderburg (1979)
- Sonderburg II (1979)
- Sorsa (1898)
- Southern Cross (1955)
- Speedy (2000)
- Stadsgården 1 (1897)
- Stadt Kappeln (1981)
- Stadt Kiel (1934)
- Standard (1922)
- Star Express (1971)
- Stellan (1955)
- Stena Finlandica (1972)
- Stockholm (1931)
- Stockholm (1948)
- Stockholm-Södra Lidingön (1894)
- Stockholms Ström 2 (1894)
- Storskär (1908)
- Strande (1984)
- Strilborg (1957)
- Strängnäs Express (1908)
- Sujjaus (2000)
- Suncoast (1956)
- Sundet (1971)
- Sundbuss Erasmus (1971)
- Sundbuss Jeppe (1974)
- Sundbuss Pernille (1981)
- Sundbuss Pernille II (1965)
- Sunnan II (1906)
- Sunrise (1960)
- Suomen Neito (1963)
- Suomi-1 (1891)
- Supercat (2000)
- Supercat 17 (1996)
- Superjet 18 (1996)
- Suur-Saimaa (1904)
- Suvi-Tuuli (1962)
- Svalan (1984)
- Svanetiya (1960)
- Svea Lejon (1981)
- Süllberg (1928)
- Sylvania (1957)
- Sælen (1992)
- Söderarm (2004)
- Søløven II (1992)