| ZIP Code | ZIP Code City/Town | ZIP Type | Average Adjusted Income(2021) |
|---|
| East Saint Louis | Standard | $131,120 |
| East Saint Louis | Standard | $141,560 |
| East Saint Louis | Standard | $174,730 |
| East Saint Louis | Standard | $128,600 |
| East Saint Louis | Standard | $159,450 |
| East Saint Louis | Standard | $136,000 |
| Fairview Heights | Standard | $343,100 |
| Belleville | Standard | $401,360 |
| Belleville | Standard | $417,960 |
| Belleville | Standard | $415,190 |
| Scott Air Force Base | Standard | $274,460 |
| Belleville | Standard | $394,440 |
| Caseyville | Standard | $607,990 |
| Collinsville | Standard | $395,340 |
| Columbia | Standard | $404,070 |
| Dupo | Standard | $325,150 |
| East Carondelet | Standard | $172,400 |
| Freeburg | Standard | $361,150 |
| Lebanon | Standard | $379,280 |
| Lenzburg | Standard | $143,740 |
| Marissa | Standard | $316,050 |
| Mascoutah | Standard | $354,620 |
| Millstadt | Standard | $432,800 |
| New Athens | Standard | $361,180 |
| New Baden | Standard | $320,430 |
| O'Fallon | Standard | $382,050 |
| Smithton | Standard | $421,460 |
| Trenton | Standard | $337,910 |
| Waterloo | Standard | $429,570 |
Source: US Internal Revenue Service