List of Ohio area codes
| Area code | Year created | Parent NPA | Overlay | Numbering plan area |
| 216 | 1947 | – | – | Cleveland |
| 330 | 1996 | 216 | 234/330 | Akron, Canton, Youngstown, and Warren |
| 234 | 2000 | 330 | 234/330 | Akron, Canton, Youngstown, and Warren |
| 440 | 1997 | 216 | 436/440 | Part of Northeast Ohio including parts of the Cleveland rate center |
| 436 | 2024 | 440 | 436/440 | Part of Northeast Ohio including parts of the Cleveland rate center |
| 419 | 1947 | – | 419/567 | Northwest and north central Ohio including Toledo, Sandusky, and Ashland |
| 567 | 2002 | 419 | 419/567 | Northwest and north central Ohio including Toledo, Sandusky, and Ashland |
| 513 | 1947 | – | 283/513 | Southwest Ohio including Cincinnati |
| 283 | 2023 | 513 | 283/513 | Southwest Ohio including Cincinnati |
| 937 | 1996 | 513 | 326/937 | Southwestern part of Ohio including Dayton, Springfield |
| 326 | 2020 | 937 | 326/937 | Southwestern part of Ohio including Dayton, Springfield |
| 614 | 1947 | – | 380/614 | Columbus |
| 380 | 2016 | 614 | 380/614 | Columbus |
| 740 | 1997 | 614 | 220/740 | Central and southeastern Ohio except Columbus |
| 220 | 2015 | 740 | 220/740 | Central and southeastern Ohio except Columbus |