Illinois District 16

86 Very irregular

Less compact than 90% of other congressional districts.

44th least compact of 429 nationally, 10th of 17 in Illinois.

A score describes shape, not intent. Coastlines, rivers and the Voting Rights Act can all make a district irregular. How scores work

The three measures

Polsby-Popper: 0.10at least as compact as 8% of districts on this measure
Area compared with perimeter. Low for jagged or snaking edges.
Reock: 0.39at least as compact as 23% of districts on this measure
Area compared with the smallest circle around the district, counting only land. Low for stretched shapes.
Convex hull: 0.61at least as compact as 11% of districts on this measure
Area compared with a rubber band stretched around the district, counting only land. Low for bites and tentacles.

Each measure runs from 0 to 1, where 1 is a perfect circle or a shape with no dents.

The state's edge

13% of this district's border is the state's edge: a coastline, a national border or a state line. Mapmakers don't choose those lines. A ragged one, like a coastline or a river, lowers Polsby-Popper. Reock and convex hull count only the state's own land, so water and neighboring states don't count against them. More on the state's edge

Cities and towns

The largest places with people in this district, from the 2020 Census. A place split between districts shows how many of its residents live in this one.

Bloomington city33,987 of its 78,680 residents
Pekin city29,725 of its 31,731 residents
Peoria city29,184 of its 113,150 residents
Machesney Park villageall 22,950 residents
East Peoria cityall 22,484 residents
Rockford city18,358 of its 148,655 residents
Morton villageall 17,117 residents
Washington cityall 16,071 residents
Dixon cityall 15,274 residents
Loves Park city15,124 of its 23,397 residents

And 202 smaller places. 29% of this district's people live outside any city, town or named community. How places are counted

ZIP codes

254 ZIP codes have residents in this district. 114 of them are split with other districts. A percentage is the share of that ZIP code's 2020 residents who live here.

Show all 254 ZIP codes

60033 (99%)
60034 (4%)
60098 (2%)
60111 (97%)
60113
60115 (1%)
60129
60145 (6%)
60146 (99%)
60150 (4%)
60152 (2%)
60178 (3%)
60407 (65%)
60410 (31%)
60416 (99%)
60420 (5%)
60424 (99%)
60437
60444
60447 (68%)
60450 (99%)
60460 (7%)
60470
60474
60479
60481 (2%)
60518 (5%)
60530 (68%)
60541 (5%)
60553
60936 (74%)
60961 (4%)
61001
61006
61007 (63%)
61008 (25%)
61010
61011 (76%)
61012
61013 (57%)
61015
61016
61018 (95%)
61019
61020
61021
61024
61025
61028
61030
61031
61032 (2%)
61036
61038 (7%)
61039 (13%)
61041
61042
61043
61044 (18%)
61047 (97%)
61048 (85%)
61049
61050
61051 (1%)
61052
61053 (3%)
61054
61057
61059
61060
61061
61062 (1%)
61063 (83%)
61064 (98%)
61065 (99%)
61067 (19%)
61068 (99%)
61070
61071 (1%)
61072
61073
61074 (1%)
61075
61078 (8%)
61079
61080
61081 (3%)
61084
61085
61087
61088 (34%)
61089
61091
61101 (26%)
61102 (11%)
61103 (11%)
61107 (30%)
61108 (22%)
61109 (32%)
61111 (66%)
61112
61114 (40%)
61115
61233
61234
61235
61238
61240 (10%)
61241 (18%)
61243 (5%)
61250 (1%)
61254 (99%)
61258
61262 (80%)
61273 (94%)
61274
61277 (12%)
61283 (27%)
61310
61311
61313 (94%)
61314
61318
61319
61321
61323 (96%)
61324
61325
61326 (1%)
61327 (23%)
61328
61330 (93%)
61331
61332
61333
61334
61335
61336
61338
61341 (12%)
61342 (1%)
61344
61345
61346
61348 (5%)
61349
61350 (2%)
61353
61354 (1%)
61356 (92%)
61358
61360 (19%)
61361
61364
61367
61368 (99%)
61369
61370 (97%)
61374
61375
61376
61377
61378
61379
61413
61414 (10%)
61419
61421
61424
61426
61434 (4%)
61443 (2%)
61449 (74%)
61451
61465 (6%)
61468
61479
61483
61489 (2%)
61490 (97%)
61491
61516
61517 (92%)
61523
61525
61526
61528
61529 (7%)
61530
61535
61536 (12%)
61537
61540
61541
61545
61548
61550
61552
61554 (92%)
61559
61560
61561
61562
61565
61568 (91%)
61570
61571
61604 (9%)
61610
61611
61614 (29%)
61615 (62%)
61616 (2%)
61701 (3%)
61704 (74%)
61705 (83%)
61720 (93%)
61722
61724
61725
61726
61728
61729
61730
61731 (71%)
61732 (99%)
61733
61736
61737
61738
61739 (1%)
61740
61742
61743
61744
61745 (96%)
61747 (80%)
61748
61752 (99%)
61753
61755
61759 (93%)
61760
61761 (29%)
61764 (11%)
61770
61771
61772 (28%)
61774 (74%)
61776
61842 (4%)
61843 (1%)
61845 (9%)
61854 (1%)

These are the Census Bureau's ZIP code areas, which match residential ZIP codes closely. ZIP codes used only for PO boxes or a single organization aren't included. How ZIP codes are matched

2024 presidential vote

Kamala Harris 38.5%, Donald Trump 61.5%

Shares of the votes for the two of them; other candidates are left out. Illinois used the same lines in 2024, so this is added up from precinct results. A precinct split between districts is divided by its House votes, so the figures are close estimates. Where the votes come from

U.S. House

Statewide results from Illinois for the November 3, 2026 election aren't available yet.

Where this comes from

Illinois's senators

Tammy Duckworth, Democrat
Richard J. Durbin, DemocratSeat on the November 3, 2026 ballot: results aren't available yet.

Senators are elected by the whole state, so district lines don't change who they are. Senators serving as of November 6, 2026. Senators elected in November 2026 take office January 3, 2027. Where this comes from

Where it sits in Illinois

Very compact (0 to 19)
Compact (20 to 39)
Middle (40 to 59)
Irregular (60 to 79)
Very irregular (80 to 100)

Spot a problem with this district? Email us about IL-16.