R
- R.A.C. (1910–1911)
- Railsbach (1914)
- Rainier (1905–1911)
- Raleigh (1921–1922)
- Rambler (1900–1914)
- Rambler (1958–1969)
- Randall (1902–1903)
- Randall Three-Wheeler (1903–1905)
- Ranger (1907–1910)
- Ranger (1920–1922)
- Rapid (1902-1909)
- Rauch & Lang (1905–1932)
- Raulang (see Rauch & Lang)
- Rayfield (1911–1915)
- R.C.H. (1912–1915)
- Read (1913–1914)
- Reading (1910–1913)
- Reading Steamer (1901–1903)
- Real Cyclecar (1914; Real Light Car 1914-1915)
- Reber (1902–1903)
- Red Bug (1924–1930)
- Red Jacket (1904–1905)
- Reed (see Massillon)
- Rees (1921)
- Reeves (1896–1898, 1905–1912)
- Regal (1908–1918)
- Regas (1903–1905)
- Reliable Dayton (1906–1909)
- Reliance (1904–1906)
- Remington (1895, 1900–1904)
- Remington (1914–1916)
- REO (or Reo) (1905–1975)
- Republic (1910–1916)
- ReVere (1918–1926)
- Rex (1914)
- RiChard (1914–1919)
- Richelieu (1922–1923)
- Richmond (1902–1903)
- Richmond (1904–1917)
- Rickenbacker (1922–1927)
- Ricketts (1909–1911)
- Riddle (1916–1926)
- Rider-Lewis (1908–1911)
- Riker Electric (1897–1902)
- Ritz (1914–1915)
- Riviera (1907)
- R-O (see Owen)
- Roader (1911–1912)
- Roamer (1916–1929)
- Robe (1914–1915)
- Robinson (1900–1902)
- Robson (1909)
- Rochester (1901)
- Rochester (1901–1902)
- Rockaway (1902–1903)
- Rockaway (1903–1904)
- Rock Falls (1919–1925)
- Rockne (1932–1933)
- Rockway (1910–1911)
- Rockwell (1910–1911)
- Rodgers (1921)
- Roebling-Planche (1909)
- Rogers (1899–1900) (see also Steamobile)
- Rogers (1911–1912)
- Rogers & Hanford (1899–1902)
- Rollin (1924–1927)
- Rolls-Royce (1921–1935)
- Roosevelt (1929–1930)
- Roper (1860–1896)
- Ross Steamer (1905–1909)
- Ross (1915–1918)
- Rotary (1903–1905)
- Rotary (1921–1923)
- Royal Electric (1904–1905; Royal Princess 1904-1905)
- Royal Tourist (1904–1911)
- Rubay (see Leon Rubay)
- Rugby (1920s)
- Rushmobile (see Brecht)
- Russell (1903–1904)
- Rutenber (1902)
- Ruxton (1929–1930)
- R&V Knight (1920–1924)
Read more about this topic: List Of Defunct Automobile Manufacturers Of The United States