Colfax is a town in Perry Township, Clinton County, Indiana, United States. The population was 691 at the 2010 census. The town was originally known as Midway since it was a halfway point on the IC&L Railroad between Chicago and Louisville. Railways intersected north–south and east–west making Colfax a popular transfer destination. The town was renamed to honor Vice President Schuyler Colfax in 1857.