| Place Name | Opdyke |
| Place Type | Census Designated Place |
| ZIP Code(s) | 62872 |
| County | Jefferson County |
| Area Code(s) | 618 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 357 |
| Population Growth Rate (2010-19) | -7.09% |
| Majority Ethnicity | White 97% |
| Metro/Micro Stats Area | Mount Vernon, IL |
| US Congressional District(s) | Illinois 12th |
| State House Districts | 115 |
| State Senate Districts | 58 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 97% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 3% |