Founded on Jan 15, 1851, Grundy County is one of 99 counties in the state of Iowa. Historically, Grundy County was formed from Black Hawk County. The city of Grundy Center is the county seat. With FIPS code of 75, Grundy County has a population of 12,347 and area of 503 square miles (1,303 km2).
List of all cities in Grundy County, IA alphabetically
| City/Town | Postal Code | Area Code |
| Beaman, IA | 50609 | 641 |
| Conrad, IA | 50621 | 641 |
| Dike, IA | 50624 | 319 |
| Dinsdale, IA | 50669 | 319 |
| Grundy Center, IA | 50638 | 319 |
| Holland, IA | 50642 | 319 |
| Morrison, IA | 50657 | 319 |
| Reinbeck, IA | 50669 | 319 |
| Stout, IA | 50673 | 319 |
| Wellsburg, IA | 50680 | 641 |