The area coe 513 serves southwest Ohio including Cincinnati and its many suburbs as well as the cities of Hamilton, Middletown, Lebanon, Trenton, and Oxford. It formerly covered a larger area of Southwestern Ohio, which has since been split into area code 937. A new area code 283 has been assigned to overlay the current 513 area, but this has been delayed as the 513 area code has not yet been depleted of available numbers.