First Financial Bank is a regional bank headquartered in Hamilton, Ohio

Hamilton, Ohio

Hamilton is a city in Butler County, southwestern Ohio, United States. The population was 62,447 at the 2010 census. It is the county seat of Butler County. The city is part of the Cincinnati metropolitan area....

, which is in the Cincinnati, Ohio

Cincinnati, Ohio

Cincinnati is a city in the U.S. state of Ohio. Cincinnati is the county seat of Hamilton County. Settled in 1788, the city is located to north of the Ohio River at the Ohio-Kentucky border, near Indiana. The population within city limits is 296,943 according to the 2010 census, making it Ohio's...

 metropolitan area. Founded in 1863, First Financial has the eighth oldest national bank charter and has locations in Southwest Ohio, Northern Kentucky

Northern Kentucky

Northern Kentucky is the name often given to the northernmost counties in Kentucky...

, and Southeast Indiana.
First Financial acquired Irwin Financial Corp and its subsidiaries through a government assisted transaction on 09/18/2009.