| City: | Rock Island, Illinois |
| County: | Rock Island County |
| Timezone: | Central (GMT -06:00) |
| Local Time: | 8:09:52 AM |
| Population: | No Population Data |
| Area Codes: | 309 / 861 |
| Classification: | PO Box |
| Coordinates: | 41.5096, -90.5787 |
| Quick Link: |
ZIP 61204 serves as a PO Box-only assignment within Rock Island, Illinois, part of the Quad Cities metro area along the Mississippi River. This isn't an island vacation destination. It's a working Midwest city where the name comes from an island in the Mississippi that gave the community its identity.
This ZIP has zero residential population because it's a point-only assignment (MultiPoint geometry) contained within the larger ZIP 61201. All street delivery in Rock Island routes through 61201, while 61204 exists specifically for PO Box and limited downtown business addresses.
The post office maintains 197 PO Boxes and serves 146 businesses. Street addresses using 61204 are limited to two streets:
| Street | Records | Notes |
|---|---|---|
| 2nd Ave | 104 | Unit designators |
| 11th St | 50 | Unit designators |
These 154 street records all route through city carrier delivery (RouteC), indicating commercial or multi-tenant buildings in the downtown core. With 11 business establishments and 44 workers recorded here, this ZIP represents a concentrated commercial pocket.
Downtown Davenport, Iowa sits just 0.4 miles away across the Mississippi River. The nearby neighborhoods all fall on the Iowa side: Hamburg, College Square, Cork Hill, and Prospect Park. This bi-state metro area shares economic and social ties across the river, making Rock Island's downtown post office a piece of a larger regional puzzle.
Both streets have unit designators, indicating multi-tenant commercial or office buildings in the downtown core.
ZIP Code 61204 supports both business and residential activity. According to the Business Census (2024), there are 8 business establishments, employing about 28 people with an annual payroll of $2,799,000.
| # Residential Mailboxes: | 0Source: USPS |
| # Business Mailboxes: | 0Source: USPS |
| Total Delivery Receptacles: | 1,067Source: USPS |
| Single Family Delivery Units: | 0Source: USPS |
| Multi Family Delivery Units: | 0Source: USPS |
| # of Businesses: | 8Source: CBP |
| 1st Quarter Payroll: | $671,000Source: CBP |
| Annual Payroll: | $2,799,000Source: CBP |
| # of Employees: | 28Source: CBP |
ZIP Code 61204 is located in Rock Island County, Illinois, within the Davenport-Moline-Rock Island, IA-IL Metropolitan Statistical Area (CBSA 19340) and Illinois's 17th Congressional District. This Metro area has a population of 379,690 people, about 0.00% of whom live in ZIP Code 61204. It covers 0 sq mi of land and a water area of 0 sq mi.
| CBSA Name: | Davenport-Moline-Rock Island, IA-ILSource: Census |
| CBSA Number: | 19340Source: Census |
| CBSA Type: | MetroSource: Census |
| CBSA Division: | --Source: Census |
| CBSA Population: | 379,690Source: Census |
| MSA: | Davenport-Moline-Rock Island, IA-IL MSASource: Census |
| Land Area: | --Source: Census |
| Water Area: | --Source: Census |
| Congressional District: | 17Source: USPS |
| Congressional Land Area: | 6933.08 sq miSource: Census |
| PMSA: | --Source: Census |
| Intro Date: | < 2004-10Source: ZIP-Codes.com |
| Place FIPS Code: | 1765078Source: Census |
| Place Name: | Rock Island city; IllinoisSource: Census |
We could not locate which school district 61204 belongs to, but we will update this once new district data is released. There are no public schools nor private schools with a mailing address in this ZIP Code. Listing Nearby schools instead. It also has 6 colleges, universities or post secondary education institutions nearby which would be a short commute to.
Our sources include trusted federal and licensed data from the United States Postal Service, U.S. Census Bureau, U.S. Geological Survey, Centers for Medicare & Medicaid Services, and the National Center for Education Statistics, along with proprietary datasets created by ZIP-Codes.com. Data last updated on February 1, 2026.