The list is the FIPS codes of Illinois counties. All the FIPS codes are starting with 17.
| County | FIPS Code |
| Adams | 17001 |
| Alexander | 17003 |
| Bond | 17005 |
| Boone | 17007 |
| Brown | 17009 |
| Bureau | 17011 |
| Calhoun | 17013 |
| Carroll | 17015 |
| Cass | 17017 |
| Champaign | 17019 |
| Christian | 17021 |
| Clark | 17023 |
| Clay | 17025 |
| Clinton | 17027 |
| Coles | 17029 |
| Cook | 17031 |
| Crawford | 17033 |
| Cumberland | 17035 |
| De Kalb | 17037 |
| De Witt | 17039 |
| Douglas | 17041 |
| Du Page | 17043 |
| Edgar | 17045 |
| Edwards | 17047 |
| Effingham | 17049 |
| Fayette | 17051 |
| Ford | 17053 |
| Franklin | 17055 |
| Fulton | 17057 |
| Gallatin | 17059 |
| Greene | 17061 |
| Grundy | 17063 |
| Hamilton | 17065 |
| Hancock | 17067 |
| Hardin | 17069 |
| Henderson | 17071 |
| Henry | 17073 |
| Iroquois | 17075 |
| Jackson | 17077 |
| Jasper | 17079 |
| Jefferson | 17081 |
| Jersey | 17083 |
| Jo Daviess | 17085 |
| Johnson | 17087 |
| Kane | 17089 |
| Kankakee | 17091 |
| Kendall | 17093 |
| Knox | 17095 |
| La Salle | 17099 |
| Lake | 17097 |
| Lawrence | 17101 |
| Lee | 17103 |
| Livingston | 17105 |
| Logan | 17107 |
| Macon | 17115 |
| Macoupin | 17117 |
| Madison | 17119 |
| Marion | 17121 |
| Marshall | 17123 |
| Mason | 17125 |
| Massac | 17127 |
| McDonough | 17109 |
| McHenry | 17111 |
| McLean | 17113 |
| Menard | 17129 |
| Mercer | 17131 |
| Monroe | 17133 |
| Montgomery | 17135 |
| Morgan | 17137 |
| Moultrie | 17139 |
| Ogle | 17141 |
| Peoria | 17143 |
| Perry | 17145 |
| Piatt | 17147 |
| Pike | 17149 |
| Pope | 17151 |
| Pulaski | 17153 |
| Putnam | 17155 |
| Randolph | 17157 |
| Richland | 17159 |
| Rock Island | 17161 |
| Saline | 17165 |
| Sangamon | 17167 |
| Schuyler | 17169 |
| Scott | 17171 |
| Shelby | 17173 |
| St Clair | 17163 |
| Stark | 17175 |
| Stephenson | 17177 |
| Tazewell | 17179 |
| Union | 17181 |
| Vermilion | 17183 |
| Wabash | 17185 |
| Warren | 17187 |
| Washington | 17189 |
| Wayne | 17191 |
| White | 17193 |
| Whiteside | 17195 |
| Will | 17197 |
| Williamson | 17199 |
| Winnebago | 17201 |
| Woodford | 17203 |
All codes are cited from United States Department of Agriculture [28].