The cornerstone of the new school was laid on March 17, 1883, at Fourth and Euclid in Ontario; it opened on October 15, 1885.

When Ontario High school opened to students from Upland in 1911, its present name was adopted.

In 1916, the Chaffey Junior College of Agriculture was added as a postgraduate department to the high school.

In 2017, Chaffey was named a top 10 community college in the nation by the Aspen Institute.

[7] The college’s passage of Measure P in 2018 allowed Chaffey to make repairs, upgrades and improvements at its three campuses.