Founded in 1825, Peoria County is one of 102 counties in the state of Illinois. Historically, Peoria County was formed from Fulton County. The city of Peoria is the county seat. With FIPS code of 143, Peoria County has a population of 179,432 and area of 618 square miles (1,601 km2).
List of all cities in Peoria County, IL alphabetically
| City/Town | Postal Code | Area Code |
| Alta, IL | 61615 | 309 |
| Bartonville, IL | 61607 | 309 |
| Bellevue, IL | 61604 | 309 |
| Bellview, IL | 61604 | 309 |
| Bradley University, IL | 61625 | 309 |
| Brimfield, IL | 61517 | 309 |
| Caterpillar Inc, IL | 61629 | 309 |
| 61630 | 309 | |
| Chillicothe, IL | 61523 | 309 |
| Cramers, IL | 61529 | 309 |
| Dunlap, IL | 61525 | 309 |
| East Peoria, IL | 61630 | 309 |
| 61635 | 309 | |
| Edelstein, IL | 61526 | 309 |
| Edgewater Terrace, IL | 61523 | 309 |
| Edwards, IL | 61528 | 309 |
| El Vista, IL | 61604 | 309 |
| Elmore, IL | 61451 | 309 |
| Elmwood, IL | 61529 | 309 |
| Galena Knolls, IL | 61523 | 309 |
| Glasford, IL | 61533 | 309 |
| Great Central Ins Co, IL | 61633 | 309 |
| Greater Peoria Airport, IL | 61607 | 309 |
| Hanna City, IL | 61536 | 309 |
| High Meadows, IL | 61607 | 309 |
| Hollis, IL | 61607 | 309 |
| Holmes Center, IL | 61523 | 309 |
| I L Central College, IL | 61635 | 309 |
| Il Mutual Life & Casualty, IL | 61634 | 309 |
| Keystone Steel and Wire, IL | 61641 | 309 |
| Kickapoo, IL | 61528 | 309 |
| Kingston Mine, IL | 61539 | 309 |
| 61539 | 309 | |
| Komatsu Dresser, IL | 61639 | 309 |
| Lake Camelot, IL | 61547 | 309 |
| Lake Lancelot, IL | 61547 | 309 |
| Lake of the Woods, IL | 61525 | 309 |
| Laura, IL | 61451 | 309 |
| Lawn Ridge, IL | 61526 | 309 |
| Mapleton, IL | 61547 | 309 |
| Mardell Manor, IL | 61607 | 309 |
| Methodist Hospital, IL | 61636 | 309 |
| Monica, IL | 61559 | 309 |
| Mossville, IL | 61552 | 309 |
| North Hampton, IL | 61523 | 309 |
| Northwoods Shop Center, IL | 61613 | 309 |
| Norwood, IL | 61604 | 309 |
| Orchard Mines, IL | 61607 | 309 |
| Peoria, IL | 61601 | 309 |
| 61602 | 309 | |
| 61603 | 309 | |
| 61604 | 309 | |
| 61605 | 309 | |
| 61606 | 309 | |
| 61607 | 309 | |
| 61612 | 309 | |
| 61613 | 309 | |
| 61614 | 309 | |
| 61615 | 309 | |
| 61616 | 309 | |
| 61625 | 309 | |
| 61629 | 309 | |
| 61630 | 309 | |
| 61633 | 309 | |
| 61634 | 309 | |
| 61635 | 309 | |
| 61636 | 309 | |
| 61637 | 309 | |
| 61638 | 309 | |
| 61639 | 309 | |
| 61641 | 309 | |
| 61643 | 309 | |
| 61650 | 309 | |
| 61651 | 309 | |
| 61652 | 309 | |
| 61653 | 309 | |
| 61654 | 309 | |
| 61655 | 309 | |
| 61656 | 309 | |
| Peoria Heights, IL | 61616 | 309 |
| Peoria Journal Star, IL | 61643 | 309 |
| Pottstown, IL | 61614 | 309 |
| Princeville, IL | 61559 | 309 |
| Renchville, IL | 61523 | 309 |
| Replacement Lens Inc, IL | 61638 | 309 |
| Rome, IL | 61562 | 309 |
| Rome Heights, IL | 61523 | 309 |
| Rosefield, IL | 61529 | 309 |
| Saint Francis Hospital, IL | 61637 | 309 |
| Smithville, IL | 61536 | 309 |
| South Rome, IL | 61523 | 309 |
| Southport, IL | 61517 | 309 |
| Trivoli, IL | 61569 | 309 |
| Tuscarora, IL | 61607 | 309 |
| Vets Row, IL | 61523 | 309 |
| Vonachen Knolls, IL | 61523 | 309 |
| West Hallock, IL | 61526 | 309 |
| West Peoria, IL | 61604 | 309 |
| Westinghouse Air Brake, IL | 61639 | 309 |