Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Tenmile Creek | Stream | | Hamilton | 38 01 04 N | 088 27 41 W |
| Tenmile Creek | Stream | | Tazewell | 40 43 48 N | 089 32 50 W |
| Tenmile School | School | 146 | Tazewell | 40 43 59 N | 089 31 18 W |
| Tennessee | Populated Place | 209 | McDonough | 40 24 43 N | 090 50 21 W |
| Tennessee Cemetery | Cemetery | 199 | Montgomery | 39 14 34 N | 089 08 33 W |
| Tennessee School (historical) | School | 204 | McDonough | 40 24 23 N | 090 51 51 W |
| Tennessee School (historical) | School | 202 | Montgomery | 39 15 05 N | 089 09 10 W |
| Tennessee School (historical) | School | 150 | Wayne | 38 35 08 N | 088 33 50 W |
| Tennessee United Methodist Church | Church | 209 | McDonough | 40 24 42 N | 090 50 13 W |
| Tennyson School | School | 183 | Cook | 41 53 12 N | 087 41 49 W |
| Tenrikyo West Chicago Church | Church | 184 | Cook | 41 57 00 N | 087 39 30 W |
| Tenstrike Mine | Mine | 230 | Jo Daviess | 42 24 36 N | 090 28 00 W |
| Tenth Avenue Park | Park | 216 | Winnebago | 42 15 19 N | 089 05 05 W |
| Tenth Avenue Playground Pool | Park | 217 | Winnebago | 42 15 21 N | 089 05 03 W |
| Teple School (historical) | School | 296 | McHenry | 42 26 40 N | 088 29 28 W |
| Terada Park | Park | 247 | Cook | 42 01 34 N | 088 06 05 W |
| Terminal Park | Park | 192 | Cook | 42 03 06 N | 087 44 28 W |
| Terminals Building | Building | 180 | Cook | 41 52 29 N | 087 37 44 W |
| Terpening Cemetery | Cemetery | 230 | Warren | 40 59 03 N | 090 30 38 W |
| Terra Cotta | Populated Place | 249 | McHenry | 42 16 54 N | 088 18 02 W |
| Terra Cotta School | School | 262 | McHenry | 42 17 04 N | 088 17 16 W |
| Terra Museum | Building | 179 | Cook | 41 53 40 N | 087 37 29 W |
| Terrace Elementary School | School | 198 | Cook | 42 02 21 N | 087 55 03 W |
| Terrace Hill Golf Course | Locale | 271 | McHenry | 42 10 20 N | 088 21 35 W |
| Terrace Park | Park | 169 | Peoria | 40 44 10 N | 089 33 11 W |
| Terrace View Park | Park | 213 | DuPage | 41 53 44 N | 088 01 15 W |
| Terrace View School | School | 226 | Winnebago | 42 21 45 N | 089 02 00 W |
| Terrapin Ridge | Ridge | 294 | Jo Daviess | 42 19 00 N | 090 12 17 W |
| Terrapin Ridge Cemetery | Cemetery | 166 | Madison | 38 39 27 N | 089 48 24 W |
| Terrapin Ridge School (historical) | School | 171 | Bond | 38 54 07 N | 089 30 36 W |
| Terrapin Ridge School (historical) | School | 313 | Jo Daviess | 42 18 42 N | 090 11 12 W |
| Terre Haute | Populated Place | 216 | Henderson | 40 39 59 N | 090 58 53 W |
| Terre Haute Cemetery | Cemetery | 216 | Henderson | 40 40 25 N | 090 58 53 W |
| Terrell Elementary School (historical) | School | 183 | Cook | 41 47 45 N | 087 37 33 W |
| Terry Creek | Stream | | Kankakee | 41 14 11 N | 088 05 43 W |
| Terry Park | Park | 198 | Macoupin | 39 26 39 N | 089 58 19 W |
| Terry Spring | Spring | 124 | Monroe | 38 24 40 N | 090 14 50 W |
| Terry Town Nursery School and Kindergarten | School | 184 | Cook | 41 53 45 N | 087 43 15 W |
| Tesla Alternative High School for Pregnant Girls | School | 181 | Cook | 41 46 25 N | 087 35 39 W |
| Test Bridge | Bridge | 151 | Brown | 39 52 03 N | 090 48 33 W |
| Tester School | School | 196 | Montgomery | 39 20 00 N | 089 25 11 W |
| Testoni Farms Airport | Airport | 205 | Livingston | 41 01 15 N | 088 39 12 W |
| Teton Park | Park | 200 | Cook | 42 03 16 N | 087 54 39 W |
| Teutopolis | Populated Place | 185 | Effingham | 39 07 59 N | 088 28 19 W |
| Teutopolis Grade School | School | 184 | Effingham | 39 07 57 N | 088 28 08 W |
| Teutopolis High School | School | 183 | Effingham | 39 07 44 N | 088 29 13 W |
| Teutopolis Post Office | Post Office | 184 | Effingham | 39 07 57 N | 088 28 26 W |
| Tevealt Cemetery | Cemetery | 129 | Lawrence | 38 49 31 N | 087 31 53 W |
| Tex Landing Strip | Airport | 204 | Christian | 39 21 25 N | 089 03 32 W |
| Texas Christian Church | Church | 222 | De Witt | 40 05 38 N | 088 59 22 W |
| Texas Chute | Channel | 141 | Adams | 39 52 21 N | 091 25 52 W |
| Texas City | Populated Place | 113 | Saline | 37 52 42 N | 088 23 36 W |
| Texas Junction | Populated Place | 115 | Jackson | 37 45 35 N | 089 19 24 W |
| Texas School (historical) | Locale | 211 | De Witt | 40 05 06 N | 088 58 28 W |
| Texas School (historical) | School | 205 | Adams | 40 10 08 N | 091 09 17 W |
| Texas School (historical) | School | 206 | Peoria | 40 43 35 N | 089 52 56 W |
| Texas Station Cemetery | Cemetery | 214 | Peoria | 40 43 49 N | 089 52 13 W |
| Texas Townhall | Building | 220 | De Witt | 40 05 17 N | 088 57 54 W |
| Texico | Populated Place | 156 | Jefferson | 38 26 22 N | 088 53 49 W |
| Texler Cemetery | Cemetery | 167 | Jasper | 38 58 49 N | 088 17 04 W |
| Thabor Hall | Building | 211 | Lake | 42 14 01 N | 087 49 48 W |
| Thacker Airport | Airport | 221 | McLean | 40 43 23 N | 088 45 47 W |
| Thacker Hollow | Valley | | Gallatin | 37 38 05 N | 088 17 55 W |
| Thackeray | Populated Place | 159 | Hamilton | 38 07 12 N | 088 27 11 W |
| Thackeray Church (historical) | Church | 153 | Hamilton | 38 06 52 N | 088 28 47 W |
| Thackeray Oil Field | Oilfield | 157 | Hamilton | 38 05 57 N | 088 25 18 W |
| Thaddeus Stubblefield Grove Nature Preserve | Park | 210 | McLean | 40 21 13 N | 089 07 53 W |
| Thai Buddhist Temple | Church | 182 | Cook | 41 53 59 N | 087 40 48 W |
| Thai Culture Center | Building | 189 | Cook | 41 45 18 N | 087 47 48 W |
| Thalia Hall | Building | 182 | Cook | 41 51 28 N | 087 39 26 W |
| Tharpe Cemetery (historical) | Cemetery | 158 | Tazewell | 40 34 02 N | 089 38 14 W |
| Thatcher Cemetery | Cemetery | 265 | Kane | 41 55 08 N | 088 33 35 W |
| Thatcher School (historical) | School | 262 | Kane | 41 55 30 N | 088 33 42 W |
| Thatcher Woods | Woods | 187 | Cook | 41 53 42 N | 087 49 50 W |
| Thatcher Woods Glen | Park | 185 | Cook | 41 53 34 N | 087 49 47 W |
| Thatcher Woods Shopping Center | Locale | 191 | Cook | 41 56 10 N | 087 50 33 W |
| Thawville | Populated Place | 210 | Iroquois | 40 40 33 N | 088 06 58 W |
| Thawville Cemetery | Cemetery | 207 | Iroquois | 40 40 35 N | 088 06 04 W |
| Thayer | Populated Place | 196 | Sangamon | 39 32 17 N | 089 45 47 W |
| Thayer J Hill Middle School | School | 216 | DuPage | 41 47 26 N | 088 11 56 W |
| Thayer School (historical) | School | 267 | McHenry | 42 24 51 N | 088 26 07 W |
| The Academy | School | 181 | Cook | 41 47 57 N | 087 35 18 W |
| The Academy | School | 183 | Cook | 41 52 50 N | 087 37 35 W |
| The Adwell Corporation Airport | Airport | 146 | Adams | 40 09 00 N | 091 30 01 W |
| The Adwell Corporation Airport | Airport | 129 | Greene | 39 20 50 N | 090 36 09 W |
| The Annex of Schaumburg Shopping Center | Locale | 243 | Cook | 42 02 53 N | 088 05 05 W |
| The Bayou | Gut | 106 | White | 37 55 57 N | 088 07 55 W |
| The Belden | Building | 183 | Cook | 41 55 26 N | 087 38 21 W |
| The Bend School (historical) | School | 189 | Whiteside | 41 44 33 N | 089 50 06 W |
| The Berghoff | Building | 182 | Cook | 41 52 45 N | 087 37 42 W |
| The Body Politic Theatre | Building | 183 | Cook | 41 55 24 N | 087 38 44 W |
| The Brewster | Building | 181 | Cook | 41 55 59 N | 087 38 30 W |
| The Bryman School | School | 181 | Cook | 41 52 48 N | 087 37 46 W |
| The Burg | Populated Place | 278 | Lee | 41 42 23 N | 089 05 55 W |
| The Bush (subdivision) | Populated Place | 178 | Cook | 41 44 31 N | 087 34 08 W |
| The Calvary Baptist Church | Church | 182 | Cook | 41 44 45 N | 087 34 32 W |
| The Cave In | Basin | 134 | Calhoun | 38 57 54 N | 090 39 55 W |
| The Center Shopping Center | Locale | 218 | Cook | 41 28 59 N | 087 40 45 W |
| The Chancellory Business Park | Locale | 209 | DuPage | 41 59 23 N | 087 59 09 W |
| The Chicago-Salem Church | Church | 182 | Cook | 41 48 30 N | 087 38 36 W |
| The Chicagoan | Building | 179 | Cook | 41 53 47 N | 087 37 33 W |
| The Children Village | School | 182 | Cook | 41 43 50 N | 087 36 15 W |
| The Childrens House | School | 182 | Cook | 41 59 24 N | 087 41 30 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 214 | Christian | 39 23 09 N | 089 05 31 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 183 | Cook | 41 58 26 N | 087 43 33 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 182 | Cook | 41 55 41 N | 087 42 32 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 190 | Cook | 42 04 44 N | 087 44 34 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 180 | Cook | 41 47 54 N | 087 35 52 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 253 | Cook | 42 01 37 N | 088 06 48 W |
| The Church of Jesus Christ of Latter Day Saints | Church | 199 | Fulton | 40 33 34 N | 090 00 55 W |