John Putnam Chapin (born: April 21, 1810 in Bradford, Vermont; died: July 27, 1864; buried in Graceland Cemetery) served as mayor of Chicago, Illinois (1846-1847) for the Whig Party.

Chapin arrived in Chicago from New Hampshire in 1832 and became a member of the wholesale and retail merchants firm Wadsworth, Dyer & Chapin.