| Locality | Post Code |
|---|---|
| Bellevue, Eaton | 49021 |
| Charlotte, Eaton | 48813 |
| Dimondale, Eaton | 48821 |
| Eaton Rapids, Eaton | 48827 |
| Grand Ledge, Eaton | 48837 |
| Lake Odessa, Eaton | 48849 |
| Lansing, Eaton | 48917 |
| Mulliken, Eaton | 48861 |
| Nashville, Eaton | 49073 |
| Olivet, Eaton | 49076 |
| Onondaga, Eaton | 49264 |
| Potterville, Eaton | 48876 |
| Springport, Eaton | 49284 |
| Sunfield, Eaton | 48890 |
| Vermontville, Eaton | 49096 |