S
- Saginaw (1914)
- Saginaw Eight (1916)
- Saginaw Speedster
- Salisbury (1895)
- Salter (1909–1915)
- Salvador (1914; S-J-R 1915-1916)
- Sampson (1904, 1911)
- Sandusky (1902–1904)
- Santos Dumont (1902–1904)
- Saturn (1990–2010)
- Saxon (1913–1923)
- Sayers (1917–1924)
- Schacht (1904–1913)
- Schaum (1901–1905)
- Schoening (1895)
- Scott (1900–1901, 1903)
- Scott (1901–1904)
- Scott (1908)
- Scott-Newcomb (1920–1921)
- Scripps-Booth (1913–1923)
- Searchmont (1900–1903)
- Sears (1905–1915)
- Sebring (1910–1912)
- Sekine (1923)
- Selden (1907–1914)
- Sellers (1909–1912)
- Senator (1907–1910)
- Senator (1912)
- Seneca (1917–1924)
- Serpentina (1915)
- Serrifile (1921–1922)
- Seven Little Buffaloes (1909)
- Severin (1920–1921)
- S.G.V. (1911–1915)
- Shad-Wyck (1917–1923)
- Shain (see Rockaway)
- Sharon (1915)
- Sharp Arrow (1908–1910)
- Shaum (see Schaum)
- Shaw (1920–1921)
- Shawmobile (1908–1930)
- Shawmut (1906–1908)
- Shelby (1903)
- Sheridan (1920–1921)
- Shoemaker (1906–1908)
- Sibley (1910–1911)
- Signet (see Fenton)
- Silent-Knight (1905–1907)
- Silent Sioux (see Fawick Flyer)
- Silver (1914–1919)
- Silver-Knight (Silver model)
- Simplex (1907–1919)
- Simplicity (1907–1911)
- Simplo (1908–1909)
- Sinclair-Scott (1904-circa 1907)
- Singer (1914–1920)
- Single Center (1906–1908)
- Sintz (1899–1904)
- Skelton (1920–1922)
- Skene (1900–1901)
- Skorpion (1952–1954)
- S&M (1913)
- S&M Simplex (1904–1907)
- Smith (1902–1917; Great Smith 1907-1911)
- Smith & Mabley (see S&M Simplex)
- Smith Flyer (1915–1919)
- S-N (see Scott-Newcomb)
- Snyder (1908–1909)
- Snyder (1914)
- Sommer (1904–1905)
- Sommer (1910–1911)
- Soules (1905–1908)
- South Bend (1913–1914)
- Southern (1906–1908)
- Southern Six (1920)
- Sovereign (1906–1907)
- Spacke (1919)
- Spaulding (1902–1903)
- Spaulding (1910–1916)
- Speedway (1904–1905)
- Speedwell (1907–1914)
- Spencer (1921–1922)
- Spencer Steamer (1862, 1901–1902)
- Sperry Electric (1898–1901)
- Sphinx (1914–1916)
- Spoerer (1908–1914)
- Springer (1903–1905)
- Springfield (1900–1901)
- Springfield (1907–1910)
- Sprite (1914)
- Squier (1899)
- S & S (1924–1929)
- Stafford (1908–1915)
- Stammobile (1900–1901)
- Standard (1904–1908)
- Standard (1912–1923)
- Standard Six (1909–1910)
- Standard 8 (see Standard)
- Standard Electrique (or Standard Electric) (1911–1915)
- Standard Steam Car (1920–1921)
- Stanley (1907–1910)
- Stanley (1910–1911)
- Stanley Steamer (1897–1927)
- Stanley Whitney (1899) (see McKay Steamer)
- Stanton (1900–1901)
- Stanwood (1920–1922)
- Star (1902–1904)
- Star (1907–1908)
- Star (1908–1909)
- Star (1922–1928)
- Starin (1903–1904)
- States (1916–1918)
- Staver (1907–1914)
- Steamobile (1900–1902)
- Stearns (1898–1911; Stearns-Knight 1912-1929)
- Stearns Electric (1899–1900; Stearns Steamer 1901-1903)
- Steco (1914)
- Steel Swallow (1907–1908)
- Stephens (1917–1924)
- Sterling Steamer (1901-1902)
- Sterling (1909–1911)
- Sterling (1915–1916)
- Sterling-Knight (1920–1926)
- Sterling-New York (1916)
- Stevens-Duryea (1901–1915,1919–1927)
- Stewart (1915-1916)
- Stewart-Coats (1922)
- Stickney Motorette (1914)
- Stilson (1907–1909)
- St. Joe (1908)
- St. Louis (1899–1907)
- Stoddard-Dayton (1904–1913)
- Storck Steamer (1901–1902)
- Storms Electric (1915)
- Stout Scarab (1932–1946)
- Strathmore (1899–1901)
- Stratton (1909)
- Stratton-Bliss (1922)
- Streator (see Halladay)
- Stringer (1899–1902)
- Strobel & Martin (see S&M)
- Strong & Rogers Electric (1900–1901)
- Strouse (see S.R.K.)
- Studebaker (1902–1963)
- Studebaker-Garford (1903–1911)
- Studillac (1953–1955)
- Sturges Electric (see Morrison Electric)
- Sturtevant (1905–1907)
- Stutz (1911–1935)
- Stutz (1968–1987)
- Stuyvesant (1911–1912)
- Suburban (1911–1912)
- Success (1906–1909)
- Sultan (1908–1912)
- Summit (1907–1909)
- Sun (1916–1917)
- Sun (1921–1922)
- Sunset (1900–1913)
- Synnestvedt Electric (1904–1905)
- Syracuse (1899–1903)
Read more about this topic: List Of Defunct Automobile Manufacturers Of The United States