Washington County, Missouri ZIP codes
10 ZIP codes are in Washington County, plus 6 that cross in from neighboring counties.
- ZIP codes
- 10
- Population in these ZIPs
- 21,955
- Avg. median income
- $57,400population-weighted
- Cities & towns
- 10
Click anywhere on the map to see which ZIP code it's in.
ZIP codes in Washington County
| ZIP code | City | Population | Median income | Typical home value |
|---|---|---|---|---|
| 63030 | Fletcher | 557 | $91,042 | $183,300 |
| 63071 | Richwoods | 1,113 | $44,853 | $225,100 |
| 63622 | Belgrade | 764 | $31,750 | — |
| 63626 | Blackwell | 588 | $82,599 | $285,900 |
| 63630 | Cadet | 4,006 | $52,482 | $209,900 |
| 63631 | Caledonia | 544 | $74,211 | $243,900 |
| 63648 | Irondale | 1,858 | $51,765 | $195,300 |
| 63660 | Mineral Point | 2,784 | $51,410 | $170,400 |
| 63664 | Potosi | 9,693 | $61,216 | $197,500 |
| 63674 | Tiff | 48 | — | — |
ZIP codes partly in Washington County
These ZIP codes are mostly in a neighboring county but cover part of Washington County.
| ZIP code | City | County | Population | Median income | Typical home value |
|---|---|---|---|---|---|
| 63020 | De Soto | Jefferson County | 20,166 | $70,824 | $244,900 |
| 63080 | Sullivan | Franklin County | 13,124 | $66,541 | $207,000 |
| 63624 | Bismarck | St. Francois County | 3,447 | $41,984 | $128,700 |
| 63628 | Bonne Terre | St. Francois County | 16,416 | $63,602 | $204,200 |
| 65441 | Bourbon | Crawford County | 5,028 | $65,050 | $219,800 |
| 65565 | Steelville | Crawford County | 4,845 | $50,277 | $209,000 |
Population and median household income: ACS 2020–2024 5-year estimates. Typical home value: Zillow Home Value Index (September 2026) where available, otherwise the ACS median owner-reported value. "PO Box" marks ZIP codes with no delivery area of their own. Methodology
Cities and towns in Washington County
Nearby counties
Frequently asked questions
How many ZIP codes are in Washington County, Missouri?
10 ZIP codes are mainly in Washington County, and 6 more ZIP codes from neighboring areas reach partly into it.
What cities are in Washington County?
ZIP codes in Washington County use the city names Belgrade, Blackwell, Cadet, Caledonia, Fletcher, Irondale, Mineral Point, Potosi, Richwoods and Tiff.