| Official Zip Code Name | Fairfield |
| Zip Code State | Iowa |
| Primary County: | Jefferson |
| Area Code | 641 |
| Current Population: | 37081 |
| Racial Majority: | White 62.49% |
| Median Household Income | $55618 |
| Average Adjusted Gross Income | $89060 |
| Time Zone: | 6 |
| Elevation Range | 767 ft. |
| Area | 175.544 Sqm. |
| Coordinates(Y,X) | 41.024981, -91.921848 |