The original town of Ontario started as a settlement on the trail between Mansfield and Bucyrus. In 1834, the combination of that settlement, another small settlement known as New Castle and additional land to be the east and west became the Village of Ontario. In 1958, after General Motors located a stamping plant in Springfield Township, Ontario residents voted to incorporate the village. Several annexations have been added since that time and millions of dollars have been spent on the construction of streets, water and sewer facilities, parks and buildings accommodating the Administrative offices, Service Departments and Water Department. The Village offices have been housed in several different locations, including the “Old Library” which is now being used as a Senior Center. The Administration has been located in the Charles K. Hellinger Municipal Building since 1986.

The Ontario of today is known for the shopping district and franchise restaurants. Shopping includes the Westfield Shoppingtown Richland, with anchor stores Sears, J.C.Penney, Lazarus and Kaufmans, as well as numerous smaller shops. Other large stores located outside the mall are Kohl’s, Target, Wal-Mart, Lowe's, Home Depot, and Meijer just to name a few. Major restaurants include Olive Garden, Red Lobster, Outback Steakhouse and many others. Ontario currently has two movie theaters, an outdoor theater, and the newly constructed Cinemark 14.