The 100 Largest Companies in Illinois for 2026
If you’re searching for job opportunities in Illinois, you’ve landed in the right spot.
While a simple search for the “largest companies in Illinois” might yield a long list of well-known businesses, we present a curated overview of companies currently headquartered in Illinois, focusing specifically on their employee counts.
Before diving into the complete list of the 100 largest companies in Illinois, let’s take a closer look at the top 10:
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Allegiance Properties (Jobs)
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City Garden Waldorf School (Jobs)
-
Walgreens (Jobs)
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McDonald’s (Jobs)
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ArcelorMittal (Jobs)
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Boeing (Jobs)
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Power Construction (Jobs)
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Hyatt Hotels (Jobs)
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Alliance Boots (Jobs)
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Abbott (Jobs)
Allegiance Properties tops the list, boasting the highest number of employees among Illinois-based companies. Details will follow, but first, let’s discuss our methodology.
How We Identified the Largest Companies in Illinois
At Zippia, we maintain a comprehensive database of over 250,000 companies nationwide.
For this analysis, we focused on companies headquartered in Illinois that employ at least 100 individuals, narrowing our pool to approximately 3,000 firms.
We ranked these companies based on their current employee counts to establish the largest companies in Illinois.
Currently, Allegiance Properties leads the way with an impressive 561,720 employees.
Detailed List of the 100 Largest Companies in Illinois
| Rank |
Company |
City |
Employees |
Jobs |
| 1 |
Allegiance Properties |
Aurora |
561,720 |
Jobs |
| 2 |
City Garden Waldorf School |
Chicago |
227,925 |
Jobs |
| 3 |
Walgreens |
Deerfield |
210,500 |
Jobs |
| 4 |
McDonald’s |
Chicago |
210,000 |
Jobs |
| 5 |
ArcelorMittal |
Chicago |
209,000 |
Jobs |
| 6 |
Boeing |
Chicago |
141,582 |
Jobs |
| 7 |
Power Construction |
West Chicago |
132,583 |
Jobs |
| 8 |
Hyatt Hotels |
Chicago |
127,000 |
Jobs |
| 9 |
Alliance Boots |
Deerfield |
120,001 |
Jobs |
| 10 |
Abbott |
North Chicago |
109,000 |
Jobs |
| 11 |
Caterpillar |
Deerfield |
97,300 |
Jobs |
| 12 |
United Airlines |
Chicago |
93,000 |
Jobs |
| 13 |
JLL |
Chicago |
91,000 |
Jobs |
| 14 |
Elite Staffing |
Chicago |
90,000 |
Jobs |
| 15 |
Tenneco |
Lake Forest |
78,000 |
Jobs |
| 16 |
Veolia Environmental Services North America |
Chicago |
77,864 |
Jobs |
| 17 |
Cruises International |
Schaumburg |
77,000 |
Jobs |
| 18 |
EVRAZ North America |
Chicago |
70,000 |
Jobs |
| 19 |
KONE |
Lisle |
61,380 |
Jobs |
| 20 |
State Farm |
Bloomington |
57,672 |
Jobs |
| 21 |
Aon |
Chicago |
50,000 |
Jobs |
| 22 |
AbbVie |
North Chicago |
47,000 |
Jobs |
| 23 |
Molex |
Lisle |
45,000 |
Jobs |
| 24 |
ITW |
Glenview |
45,000 |
Jobs |
| 25 |
H Group Holding, Inc |
Chicago |
42,000 |
Jobs |
| 26 |
Omron Automation – Americas |
Hoffman Estates |
39,427 |
Jobs |
| 27 |
ADM |
Chicago |
38,100 |
Jobs |
| 28 |
ULTRA Diamonds |
Chicago |
37,000 |
Jobs |
| 29 |
Ulta Beauty |
Bolingbrook |
37,000 |
Jobs |
| 30 |
Exelon Energy |
Chicago |
33,383 |
Jobs |
| 31 |
Eagle Services |
Creve Coeur |
32,000 |
Jobs |
| 32 |
Gallagher |
Rolling Meadows |
31,013 |
Jobs |
| 33 |
FedPayments Improvement |
Chicago |
30,000 |
Jobs |
| 34 |
Abbott Diagnostics Business |
North Chicago |
30,000 |
Jobs |
| 35 |
Chicago Public Schools |
Chicago |
28,788 |
Jobs |
| 36 |
Dtz |
Chicago |
28,001 |
Jobs |
| 37 |
Danfoss |
Loves Park |
28,000 |
Jobs |
| 38 |
Medline |
Mundelein |
28,000 |
Jobs |
| 39 |
Merlin 200 |
Saint Charles |
27,000 |
Jobs |
| 40 |
Kerry Holding Co. |
Gridley |
25,255 |
Jobs |
| 41 |
Stericycle |
Bannockburn |
23,200 |
Jobs |
| 42 |
Grainger |
Lake Forest |
23,100 |
Jobs |
| 43 |
Marmon Group |
Chicago |
20,000 |
Jobs |
| 44 |
Northwestern Medicine |
Chicago |
20,000 |
Jobs |
| 45 |
OSI Group |
Aurora |
20,000 |
Jobs |
| 46 |
SCC Holding Company LLC |
Highland Park |
19,500 |
Jobs |
| 47 |
JVC |
Aurora |
19,044 |
Jobs |
| 48 |
SPi Global |
Tinley Park |
18,000 |
Jobs |
| 49 |
Dominick’s Finer Foods |
Oak Brook |
18,000 |
Jobs |
| 50 |
ABN AMRO Chicago Corporation |
Chicago |
17,813 |
Jobs |
| 51 |
Discover |
Riverwoods |
17,600 |
Jobs |
| 52 |
Astellas Pharma |
Northbrook |
17,217 |
Jobs |
| 53 |
Amsted Industries |
Chicago |
16,000 |
Jobs |
| 54 |
HSBC Bank |
Mettawa |
15,650 |
Jobs |
| 55 |
Bohler-Uddeholm |
Elgin |
15,453 |
Jobs |
| 56 |
Yaskawa America |
Waukegan |
15,287 |
Jobs |
| 57 |
Standard Companies |
Chicago |
15,200 |
Jobs |
| 58 |
Central Leasing Management Inc |
Oak Brook |
15,000 |
Jobs |
| 59 |
BPRex Healthcare Packaging Inc. |
Buffalo Grove |
15,000 |
Jobs |
| 60 |
Alight Solutions |
Lincolnshire |
15,000 |
Jobs |
| 61 |
IMS Companies |
Des Plaines |
14,000 |
Jobs |
| 62 |
United Biscuits US Inc |
Elmhurst |
13,000 |
Jobs |
| 63 |
Dyson |
Chicago |
13,000 |
Jobs |
| 64 |
Brunswick |
Mettawa |
13,000 |
Jobs |
| 65 |
Aptar |
Crystal Lake |
13,000 |
Jobs |
| 66 |
Levy Food Service Limited Partnership |
Chicago |
12,468 |
Jobs |
| 67 |
Navistar |
Lisle |
12,300 |
Jobs |
| 68 |
Flex-N-Gate |
Urbana |
12,150 |
Jobs |
| 69 |
UL |
Northbrook |
12,000 |
Jobs |
| 70 |
Nalco Holding Company |
Naperville |
11,500 |
Jobs |
| 71 |
SAS Holdings |
Bedford Park |
11,288 |
Jobs |
| 72 |
CDW |
Vernon Hills |
11,098 |
Jobs |
| 73 |
MAT Holdings |
Long Grove |
11,000 |
Jobs |
| 74 |
Keller Group |
Northfield |
10,554 |
Jobs |
| 75 |
Reyes Holdings |
Rosemont |
10,300 |
Jobs |
| 76 |
Modest Inc |
Chicago |
10,002 |
Jobs |
| 77 |
Clover Technologies Group |
Hoffman Estates |
10,001 |
Jobs |
| 78 |
Cook County Government |
Chicago |
10,001 |
Jobs |
| 79 |
Park Lane Jewelry |
Schaumburg |
10,001 |
Jobs |
| 80 |
LaSalle Bank |
Chicago |
10,001 |
Jobs |
| 81 |
AMITA Health |
Chicago |
10,001 |
Jobs |
| 82 |
Jlt Specialty Usa |
Chicago |
10,001 |
Jobs |
| 83 |
Ottawa, Illinois |
Ottawa |
10,001 |
Jobs |
| 84 |
Quaker Oats |
Chicago |
10,000 |
Jobs |
| 85 |
SCA Health |
Deerfield |
10,000 |
Jobs |
| 86 |
BGI, Inc |
Joliet |
10,000 |
Jobs |
| 87 |
Zensar Technologies |
Oak Brook |
10,000 |
Jobs |
| 88 |
Hillrom |
Chicago |
10,000 |
Jobs |
| 89 |
HUB International |
Chicago |
10,000 |
Jobs |
| 90 |
Telephone and Data Systems |
Chicago |
9,900 |
Jobs |
| 91 |
Sysmex |
Mundelein |
9,231 |
Jobs |
| 92 |
BMO Diners Club Inc |
Chicago |
9,123 |
Jobs |
| 93 |
CDK Global |
Hoffman Estates |
9,000 |
Jobs |
| 94 |
Kingpin Holdings, LLC |
Chicago |
8,841 |
Jobs |
| 95 |
Kingpin Intermediate Holdings LLC |
Chicago |
8,841 |
Jobs |
| 96 |
Zebra Technologies |
Lincolnshire |
8,800 |
Jobs |
| 97 |
Spectris plc |
Libertyville |
8,659 |
Jobs |
| 98 |
Amer Sports |
Chicago |
8,617 |
Jobs |
| 99 |
Draftfcb |
Chicago |
8,600 |
Jobs |
| 100 |
Vwr Investors Inc |
Chicago |
8,600 |
Jobs |
In conclusion, Illinois is home to a vibrant array of large companies offering diverse career opportunities. With a dynamic labor market and an emphasis on innovation, professionals seeking new roles can find a wealth of options across various industries.
