| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Meadow Green | city | Illinois | United States | 42.11 | -87.85 | 830 | |
| Meadow Heights | city | Illinois | United States | 38.69 | -89.99 | 830 | |
| Meadowbrook | city | Illinois | United States | 39.92 | -91.36 | 830 | |
| Meadowbrook | city | Illinois | United States | 38.90 | -90.01 | 830 | |
| Meadowdale Estates | city | Illinois | United States | 41.65 | -88.11 | 830 | |
| Meadowridge | city | Illinois | United States | 42.19 | -88.04 | 830 | |
| Meadows | city | Illinois | United States | 40.74 | -88.80 | 830 | |
| Meadowview | city | Illinois | United States | 41.60 | -87.93 | 830 | |
| Meadowview | city | Illinois | United States | 39.79 | -88.28 | 830 | |
| Mechanicsburg | city | Illinois | United States | 39.81 | -89.40 | 830 | |
| Media | city | Illinois | United States | 40.78 | -90.83 | 830 | |
| Medinah | city | Illinois | United States | 41.98 | -88.05 | 830 | |
| Medora | city | Illinois | United States | 39.17 | -90.14 | 830 | |
| Meeks | city | Illinois | United States | 40.00 | -87.58 | 830 | |
| Meivuda | city | Illinois | United States | 41.88 | -87.84 | 830 | |
| Meivudas | city | Illinois | United States | 41.88 | -87.84 | 830 | |
| Melody | city | Illinois | United States | 42.24 | -87.88 | 830 | |
| Melrose | city | Illinois | United States | 39.22 | -87.76 | 830 | |
| Melrose | city | Illinois | United States | 39.91 | -91.38 | 830 | |
| Melrose Park | city | Illinois | United States | 41.90 | -87.86 | 830 | |
| Melugin Grove (historical) | city | Illinois | United States | 41.71 | -89.11 | 948 | |
| Melville | city | Illinois | United States | 38.94 | -90.25 | 830 | |
| Melvin | city | Illinois | United States | 40.57 | -88.25 | 830 | |
| Melwood | city | Illinois | United States | 39.76 | -87.86 | 830 | |
| Menard | city | Illinois | United States | 37.91 | -89.84 | 351 | |
| Mendon | city | Illinois | United States | 40.09 | -91.28 | 830 | |
| Mendota | city | Illinois | United States | 41.55 | -89.12 | 830 | |
| Menominee | city | Illinois | United States | 42.49 | -90.53 | 830 | |
| Meppen | city | Illinois | United States | 39.00 | -90.60 | 830 | |
| Meredith | city | Illinois | United States | 41.90 | -88.54 | 895 | |
| Meredosia | city | Illinois | United States | 39.83 | -90.56 | 830 | |
| Meriden | city | Illinois | United States | 41.57 | -89.03 | 830 | |
| Mermet | city | Illinois | United States | 37.27 | -88.85 | 367 | |
| Merna | city | Illinois | United States | 40.52 | -88.83 | 830 | |
| Merriam | city | Illinois | United States | 38.36 | -88.28 | 413 | |
| Merrimac | city | Illinois | United States | 38.37 | -90.33 | 403 | |
| Merrionette Manor | city | Illinois | United States | 41.72 | -87.57 | 830 | |
| Merrionette Park | city | Illinois | United States | 41.68 | -87.70 | 830 | |
| Merritt | city | Illinois | United States | 39.71 | -90.42 | 830 | |
| Metamora | city | Illinois | United States | 40.79 | -89.36 | 830 | |
| Metcalf | city | Illinois | United States | 39.80 | -87.81 | 830 | |
| Metropolis | city | Illinois | United States | 37.15 | -88.73 | 301 | |
| Mettawa | city | Illinois | United States | 42.23 | -87.93 | 830 | |
| Mexico | city | Illinois | United States | 41.79 | -87.69 | 830 | |
| Meyer | city | Illinois | United States | 40.15 | -91.50 | 830 | |
| Meyer | city | Illinois | United States | 38.05 | -89.04 | 830 | |
| Meyer's Subdivision | city | Illinois | United States | 42.13 | -87.83 | 830 |