Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Scoville Institute (historical) | School | 192 | Cook | 41 53 21 N | 087 47 47 W |
| Scoville Park | Park | 193 | Cook | 41 53 22 N | 087 47 42 W |
| Scoville School (historical) | School | 183 | Peoria | 40 34 38 N | 089 51 07 W |
| Scoville Square | Building | 191 | Cook | 41 53 18 N | 087 47 42 W |
| Scraper-Moecherville | Populated Place | 214 | Kane | 41 44 47 N | 088 16 51 W |
| Scripps Park | Park | 200 | Schuyler | 40 06 55 N | 090 34 41 W |
| Scrivens School (historical) | School | 259 | Boone | 42 09 51 N | 088 48 13 W |
| Scrogin Cemetery | Cemetery | 226 | McLean | 40 38 41 N | 088 47 16 W |
| Scrub Creek | Stream | | Jo Daviess | 42 11 54 N | 090 06 27 W |
| Scrub Hill School (historical) | School | 161 | Wayne | 38 17 53 N | 088 37 37 W |
| Scuds Lake | Lake | 218 | Will | 41 33 40 N | 087 55 59 W |
| Scully Park | Park | 180 | Logan | 40 08 40 N | 089 21 51 W |
| Sculptors Guild | School | 183 | Cook | 41 56 19 N | 087 39 43 W |
| Seaborn Cemetery | Cemetery | 198 | Pike | 39 50 02 N | 090 50 31 W |
| Seabury-Western Theological Seminary | School | 182 | Cook | 42 03 25 N | 087 40 40 W |
| Seager Hall | Building | 217 | DuPage | 41 46 21 N | 088 08 35 W |
| Seager Park | Park | 222 | DuPage | 41 47 10 N | 088 07 45 W |
| Seagraves Cemetery | Cemetery | 168 | Bond | 38 53 39 N | 089 17 09 W |
| Seagraves School (historical) | School | 165 | Bond | 38 54 08 N | 089 17 37 W |
| Seal Church (historical) | Church | 113 | White | 38 00 35 N | 088 05 53 W |
| Seal Hall | Building | 212 | McDonough | 40 27 57 N | 090 41 03 W |
| Seal School (historical) | School | 112 | White | 38 00 40 N | 088 05 03 W |
| Seals Chapel Cemetery | Cemetery | 113 | White | 38 00 32 N | 088 05 58 W |
| Seaman Cemetery | Cemetery | 193 | La Salle | 41 33 15 N | 088 41 33 W |
| Seamans Pond | Lake | 130 | Morgan | 39 48 15 N | 090 34 49 W |
| Seaney Cemetery | Cemetery | 166 | Crawford | 38 56 03 N | 087 38 48 W |
| Sear's Cemetery | Cemetery | 156 | Mason | 40 10 46 N | 089 54 04 W |
| Search School (historical) | School | 201 | Iroquois | 40 41 51 N | 087 50 28 W |
| Searl Ridge Cemetery | Cemetery | 197 | Bureau | 41 19 58 N | 089 22 04 W |
| Searle Chemistry Laboratory | Building | 180 | Cook | 41 47 26 N | 087 36 03 W |
| Searle Hall | Building | 184 | Cook | 42 03 08 N | 087 40 47 W |
| Searle Park | Park | 187 | Cook | 42 01 48 N | 087 45 03 W |
| Searles School (historical) | School | 194 | Kankakee | 41 10 43 N | 087 42 04 W |
| Searls Field | Airport | 225 | Adams | 40 03 40 N | 091 02 04 W |
| Searls Memorial Park | Park | 224 | Winnebago | 42 18 00 N | 089 07 15 W |
| Searls Park Prairie Nature Preserve | Park | 222 | Winnebago | 42 17 51 N | 089 07 18 W |
| Searls RLA 59 Airport | Airport | 225 | Adams | 40 03 30 N | 091 02 10 W |
| Sears Cemetery | Cemetery | 146 | Crawford | 38 55 33 N | 087 46 42 W |
| Sears Cemetery | Cemetery | 189 | Scott | 39 43 14 N | 090 33 55 W |
| Sears Elementary School | School | 188 | Cook | 42 05 24 N | 087 43 06 W |
| Sears Grove School (historical) | School | 156 | Mason | 40 10 48 N | 089 54 15 W |
| Sears Lake | Reservoir | 233 | McLean | 40 33 18 N | 089 13 18 W |
| Sears Lake Dam | Dam | 233 | McLean | 40 33 18 N | 089 13 18 W |
| Sears Park | Park | 181 | Cook | 41 40 00 N | 087 42 28 W |
| Sears Quarry | Mine | 245 | DeKalb | 41 56 47 N | 088 39 02 W |
| Sears School (historical) | School | 206 | Kendall | 41 42 18 N | 088 30 40 W |
| Sears Tower | Building | 181 | Cook | 41 52 43 N | 087 38 09 W |
| Sears YMCA Day Care Center | School | 182 | Cook | 41 52 13 N | 087 42 23 W |
| Seass Cemetery | Cemetery | 201 | Moultrie | 39 38 39 N | 088 31 44 W |
| Seaton | Populated Place | 187 | Mercer | 41 06 08 N | 090 48 06 W |
| Seatonville | Populated Place | 189 | Bureau | 41 21 53 N | 089 16 35 W |
| Seavey Drainage Ditch | Canal | 206 | Lake | 42 13 49 N | 087 57 26 W |
| Seavey Road Run | Stream | | Kane | 41 48 38 N | 088 28 01 W |
| Seavey Road Run Green Road Branch | Stream | | Kane | 41 50 09 N | 088 26 30 W |
| Seavey Road Run Main Street Branch | Stream | | Kane | 41 49 58 N | 088 25 41 W |
| Seawards Island | Island | 181 | Jo Daviess | 42 15 31 N | 090 24 52 W |
| Seba Park | Park | 213 | Kane | 41 59 35 N | 088 17 43 W |
| Sebastopol | Populated Place | 163 | Madison | 38 42 40 N | 089 36 02 W |
| Second Baptist Church | Church | 192 | Cook | 41 52 58 N | 087 50 58 W |
| Second Baptist Church | Church | 184 | Cook | 41 37 03 N | 087 39 57 W |
| Second Baptist Church | Church | 136 | Franklin | 37 53 48 N | 088 54 17 W |
| Second Baptist Church | Church | 141 | Jefferson | 38 18 29 N | 088 54 14 W |
| Second Baptist Church | Church | 193 | Kankakee | 41 07 38 N | 087 51 11 W |
| Second Baptist Church | Church | 237 | Knox | 40 56 37 N | 090 22 09 W |
| Second Baptist Church | Church | 205 | Lee | 41 50 26 N | 089 29 14 W |
| Second Baptist Church | Church | 180 | Logan | 40 08 41 N | 089 21 35 W |
| Second Baptist Church | Church | 129 | Madison | 38 42 29 N | 090 09 18 W |
| Second Baptist Church | Church | 214 | Peoria | 40 41 57 N | 089 41 40 W |
| Second Baptist Church | Church | 231 | Stephenson | 42 18 13 N | 089 36 36 W |
| Second Baptist Church | Church | 186 | Vermilion | 40 08 24 N | 087 38 02 W |
| Second Baptist Church | Church | 165 | Will | 41 31 15 N | 088 05 02 W |
| Second Baptist Church | Church | 132 | Williamson | 37 47 42 N | 089 01 22 W |
| Second Baptist Church | Church | 132 | Williamson | 37 43 42 N | 088 56 32 W |
| Second Baptist Church (historical) | Church | 215 | McDonough | 40 27 50 N | 090 40 02 W |
| Second Baptist Church of Wheaton | Church | 236 | DuPage | 41 52 02 N | 088 05 07 W |
| Second Birth Missionary Baptist Church | Church | 182 | Cook | 41 45 42 N | 087 39 16 W |
| Second Chance Tutoring | School | 180 | Cook | 41 45 31 N | 087 34 26 W |
| Second Christian Church | Church | 224 | Winnebago | 42 17 00 N | 089 05 49 W |
| Second Church of Christ | Church | 241 | Peoria | 40 45 48 N | 089 36 09 W |
| Second Church of Christ | Church | 194 | Vermilion | 40 08 04 N | 087 36 41 W |
| Second Church of Christ Scientist | Church | 181 | Cook | 41 55 52 N | 087 38 27 W |
| Second City Day School | School | 180 | Cook | 41 52 10 N | 087 37 46 W |
| Second Congregational Church | Church | 223 | Winnebago | 42 16 28 N | 089 05 39 W |
| Second Creek | Stream | | Effingham | 39 02 02 N | 088 37 32 W |
| Second Faith Temple Church of God in Christ | Church | 183 | Cook | 41 48 21 N | 087 36 55 W |
| Second Free Baptist Church (historical) | Church | 96 | Alexander | 37 00 04 N | 089 10 25 W |
| Second General Baptist Church (historical) | Church | 140 | Jefferson | 38 18 52 N | 088 53 38 W |
| Second Little Rock Missionary Baptist Church | Church | 183 | Cook | 41 47 13 N | 087 38 31 W |
| Second Mount Calvery Missionary Baptist Church | Church | 184 | Cook | 41 45 01 N | 087 39 56 W |
| Second Mount Vernon Baptist Church | Church | 186 | Cook | 41 45 00 N | 087 40 33 W |
| Second Pentcostal Missionary Baptist Church | Church | 184 | Cook | 41 51 59 N | 087 43 24 W |
| Second Presbyterian Church | Church | 181 | Cook | 41 51 21 N | 087 37 28 W |
| Second Presbyterian Church | Church | 182 | Cook | 42 02 03 N | 087 40 39 W |
| Second Presbyterian Church | Church | 189 | Cook | 41 52 56 N | 087 47 05 W |
| Second Presbyterian Church | Church | 241 | Stephenson | 42 17 36 N | 089 37 09 W |
| Second Reformed Church | Church | 149 | Tazewell | 40 34 17 N | 089 38 29 W |
| Second Salt Creek | Stream | | Effingham | 39 08 24 N | 088 29 28 W |
| Second Samaritan Church of God | Church | 182 | Cook | 41 48 48 N | 087 38 05 W |
| Second Temple Church of Christ Holiness | Church | 182 | Cook | 41 45 59 N | 087 39 14 W |
| Second Timothy Missionary Baptist Church | Church | 183 | Cook | 41 51 30 N | 087 43 30 W |
| Second Unitarian Church of Chicago | Church | 181 | Cook | 41 56 17 N | 087 38 47 W |
| Secor | Populated Place | 223 | Woodford | 40 44 31 N | 089 08 07 W |
| Secor Cemetery | Cemetery | 219 | Woodford | 40 44 05 N | 089 07 32 W |
| Secor Church of Christ | Church | 223 | Woodford | 40 44 33 N | 089 08 19 W |
| Secor United Methodist Church | Church | 223 | Woodford | 40 44 18 N | 089 08 11 W |
| Section Cemetery | Cemetery | 223 | La Salle | 41 25 14 N | 088 39 55 W |
| Section Creek | Stream | | Fayette | 39 11 02 N | 088 56 44 W |
| Section Eight Woods Nature Preserve | Park | 100 | Pulaski | 37 18 24 N | 089 00 43 W |
| Section School (historical) | School | 215 | La Salle | 41 25 12 N | 088 39 31 W |
| Section School (historical) | School | 178 | Shelby | 39 19 03 N | 088 50 44 W |