1926 – Original route certified; originally routed along its current alignment from Oldtown to Fairborn.
March 9, 1932 – Extended north to State Route 4 approximately north of Fairborn along previously unnumbered road.
1969 – Extended north to its current terminus along previous State Route 69.
On November 9, 2012, the Clark County-Springfield Transportation Coordinating Committee announced that a roundabout would be constructed at the intersection of SR 235 and SR 41 in Pike Township, which has been the site of numerous vehicle crashes, including five fatalities from 1992 to 2013. Construction on the $1.1 million project began in June 2014 and was completed the weekend before Monday, September 15. It is the first roundabout in Clark County and is believed to be the first in Ohio with all approaches at high speed,.
1938 – Extended north to McComb along previously unnumbered road, from McComb to Hoytville along the previous alignment of State Route 186, and from Hoytville to east of Grand Rapids along a previously unnumbered road.
Future
The Ohio Department of Transportation and the Clark County-Springfield Transportation Coordinating Committee have conducted a SR 235 Corridor Management Study, examining improvements to SR 235 in Bethel Township, between US 40 to the north, and the Greene County line to the south. The study primarily covered the Park Layne section of the township. The study area has had many vehicle crashes and four pedestrian fatalities between 2007 and 2010. The road has many closely spaced commercial driveways and lacks crosswalks, among other problems. Proposed changes included a raised median with breaks only at a few major cross streets, consolidated driveways limited to right-in/right-out access, and jughandles or U-turns at each end of the corridor for turnarounds. Other proposals included U-turns at the busiest cross street, Styer Drive, roundabouts at the major cross streets and "backage" roads. Public meetings related to this study were held in September 2011 and April 2012. The projected cost of the improvements ranged from $7.4 million to $12.2 million and construction was not expected to begin until 2017 to 2020. In mid-October 2012, it was decided by the Ohio Department of Transportation and Clark County officials to make about $3 million in improvements to this stretch of SR 235, including the consolidation of driveways and the construction of cul-de-sacs. Construction is expected to begin in 2015. The development of any "backage" roads will be left to future private developers. In Xenia Township, Greene County, north of Xenia, ODOT plans to convert the intersection with US 68, SR 235's southern terminus, to a roundabout. As of summer 2020, construction is expected to begin in spring 2023 and to be completed that fall, with an estimated cost of $2 million.
