| # | Company | Employees |
|---|---|---|
| 1 |
Illinois Department of Human Servicesillinois.jobs2web.com
A large agency in Illinois with over 13,000 employees providing integrated services to promote self-sufficiency, independence, and health for individuals and communities |
2,733 |
| 2 |
Cook County Governmentcookcountyil.gov
A government entity in Cook County, IL, led by President Toni Preckwinkle, focuses on providing high-quality services and fostering thriving communities through various policy priorities |
2,502 |
| 3 |
Lake Countylakecountyil.gov
Region encompassing rural, urban, affluent suburbs, and tourist areas in northeastern Illinois along Lake Michigan and near Chicago. |
2,481 |
| 4 |
Chicago Park Districtchicagoparkdistrict.com
The company manages over 8,700 acres of green space in Chicago, offering various sports, cultural, and environmental programs for all ages |
2,361 |
| 5 |
Government Finance Officers Association (GFOA)gfoa.org
Premier association for public-sector finance professionals in the US and Canada, providing leading practices in government financial management through education and training |
2,179 |
| 6 |
Illinois Secretary of Stateilsos.gov
The Office of the Secretary of State in Illinois is a key government agency responsible for maintaining state records and providing important services to citizens |
1,545 |
| 7 |
DuPage Countydupagecounty.gov
DuPage County provides high-quality services in public safety, healthcare, infrastructure, and social services to create a desirable place for residents to live and work |
1,516 |
| 8 |
Illinois Tollwaylinktr.ee
The Illinois Tollway operates a user-fee system of interstate tollways in Northern Illinois, providing safe and efficient highways and services to customers |
895 |
| 9 |
Chicago Housing Authoritythecha.org
This organization in Chicago provides affordable housing options for low-income families through various programs, serving over 133,000 people in the city |
884 |
| 10 |
City of Evanstoncityofevanston.org
Managing a diverse lakeside community north of Chicago featuring Northwestern University, Rotary International headquarters, public schools, various business districts, and parks. |
707 |
| 11 |
US Railroad Retirement Boardrrb.gov
An independent Federal agency based in Chicago that administers retirement, survivor, unemployment, and sickness benefits for railroad workers and their families nationwide |
633 |
| 12 |
City of Napervillenaperville.il.us
The company is located in Naperville, offering a variety of amenities such as top schools, a great library system, parks, and healthcare providers in a low-crime environment |
616 |
| 13 |
The Clerk of the Circuit Court of Cook Countycookcountyclerkofcourt.org
The company provides efficient, transparent court services with exceptional service, information, and court records to Cook County citizens and judicial system participants |
590 |
| 14 |
Kane County, Illinoiskanecountyil.gov
Providing accountable, innovative, and high-quality government services to enhance health, welfare, and safety of Kane County residents. |
554 |
| 15 |
City of Elgin, ILelginil.gov
A progressive community with a strong history and diverse population, striving for a bright future through resilience, growth, and innovation |
553 |
| 16 |
Winnebago Countywincoil.gov
Winnebago County located in Illinois with a population of 295,300, is the seventh most populous county in the state |
537 |
| 17 |
Chicago Department of Public Healthchicago.gov
This organization in Chicago performs core public health functions including planning, policy, disease control, public health campaigns, marketing, and clinical services |
537 |
| 18 |
JUVENILE DETENTION CENTER
A healthcare facility located in Vernon Hills, Illinois, providing services to juvenile individuals in detention, ensuring their health and well-being |
537 |
| 19 |
DuPage County Health Departmentdupagehealth.org
The Health Department in DuPage County, IL promotes community health through services like immunizations, dental care, disease prevention, and mental health support |
515 |
| 20 |
McHenry Countymchenrycountyil.gov
Established in 1836, this Illinois county government focuses on delivering top-notch services to its residents with a commitment to quality |
498 |
| 21 |
Illinois Department of Revenuetax.illinois.gov
Administering Illinois tax laws, collecting revenues fairly and efficiently, providing funding and information to constituents, focusing on accuracy, innovation, and productivity |
489 |
| 22 |
Lake County Health Department and Community Health Centerlakecountyil.gov
Accredited public health agency focused on improving health outcomes through innovation, quality improvement, equity, and data-driven interventions in Lake County |
475 |
| 23 |
Illinois Environmental Protection Agencyepa.illinois.gov
This organization in Illinois aims to protect environmental quality and natural resources by working with businesses, governments, and citizens |
454 |
| 24 |
City of Bloomington, ILbloomingtonil.gov
Municipal government serving Bloomington, a city in Central Illinois, overseeing administrative and public services for population of 76,610 |
446 |
| 25 |
Illinois Department of Natural Resourcesdnr.illinois.gov
This company manages, conserves, and protects Illinois' natural, recreational, and cultural resources, while promoting education, science, public safety, and economic benefits statewide |
415 |
| 26 |
Champaign Countyco.champaign.il.us
Champaign County, Illinois is a hub of education, healthcare, technology, industry, and agriculture, with a history dating back to 1833 |
410 |
| 27 |
City of Aurora, ILaurora.il.us
Based in Aurora, Illinois, we are a rapidly growing suburban business serving multiple counties around Chicago since the 1960s |
404 |
| 28 |
Village of Schaumburgvillageofschaumburg.com
The company works to enhance the quality of life in Schaumburg by providing information, services, and amenities for residents, businesses, and visitors |
392 |
| 29 |
City of Jolietjoliet.gov
A vibrant city in Illinois, home to 150,000 residents, thriving businesses, and attractions County seat of Will County Located 40 miles southwest of Chicago |
379 |
| 30 |
Kendall Countykendallcountyil.gov
Leading rapidly growing county in Illinois with roots in rural farming since 1841 Experiencing exponential population growth since the 1990s |
360 |
| 31 |
City of Champaignchampaignil.gov
An inclusive community with quality of life, education, mobility, vibrant city center, sustainable design, and growing economy Visit website for more information |
333 |
| 32 |
Illinois Department of Correctionsillinois.gov
Mission-driven organization in Illinois focused on promoting positive change in offender behavior, operating reentry programs, and reducing victimization to serve justice and enhance public safety |
330 |
| 33 |
Village of Orland Park, Illinoisorlandpark.org
The company is involved in managing growth, redevelopment, and transformation of a suburb into a corporate center with focus on housing, schools, recreation, and open spaces |
325 |
| 34 |
City of Springfield Illinoisspringfield.il.us
A local government in Springfield, Illinois, known for its rich history, strong business environment, and diverse city departments serving residents and businesses |
319 |
| 35 |
Hanover Townshiphanover-township.org
We provide quality, cost-effective community-based services to enhance the quality of life for residents in Hanover Township Serving over 105,000 residents in Cook County |
314 |
| 36 |
Illinois Department of Commerce and Economic Opportunitydceo.illinois.gov
Leading economic development efforts by retaining and creating jobs, attracting businesses, fostering entrepreneurship, promoting tourism, and facilitating trade and investment |
312 |
| 37 |
Naperville Park Districtnapervilleparks.org
Established in 1966, this independent municipal agency manages over 2,500 acres with 150+ parks and facilities, offering 900+ recreational programs and events annually |
311 |
| 38 |
Peoria County Governmentpeoriacounty.gov
Peoria County oversees a range of essential services for its population, including law enforcement, public health, animal control, and veterans assistance |
307 |
| 39 |
Lake County Forest Preserve Districtlcfpd.org
Preserving natural and cultural resources through educational, recreational, and cultural opportunities while promoting environmental and fiscal responsibility in the region |
302 |
| 40 |
Forest Preserve District of DuPage Countydupageforest.org
Their purpose is to acquire, preserve, protect, and restore natural resources in the county, while offering opportunities for people to connect with nature |
273 |
| 41 |
City of Rock Islandrigov.org
The organization is a full-service community in Rock Island, part of the Quad Cities region, offering diverse housing, schools, entertainment, and recreational opportunities |
267 |
| 42 |
The City of Lake Forestcityoflakeforest.com
Municipal government in Lake Forest, Illinois, established in 1861 Serving a population of 19,375, part of the Chicago metropolitan area |
249 |
| 43 |
City of Des Plainesdesplainesil.gov
The company provides residents and businesses in Des Plaines, IL with access to transportation, amenities, and a vibrant community |
225 |
| 44 |
Village of Arlington Heightsvah.com
Municipal government entity in Arlington Heights, providing top-quality services to residents in a vibrant community with access to major transportation hubs |
222 |
| 45 |
Dept Of Human Svcesservicesaustralia.gov.au
A government department in Australia that provides services to meet people's needs at various stages of their lives |
190 |
| 46 |
Illinois Commerce Commissionlinktr.ee
Regulating and balancing consumer and utility interests, promoting competitive energy markets, overseeing utility services, transportation safety, and household moving companies |
178 |
| 47 |
Elk Grove Villageelkgrove.org
A proactive village near O'Hare International Airport with a diverse business community, modern infrastructure, low property taxes, and a highly educated workforce supporting corporate growth |
178 |
| 48 |
Village of Skokieskokie.org
A government entity in Skokie, Illinois, providing high-quality services to residents, households, and businesses through nationally accredited police, fire, public works, and health departments |
177 |
| 49 |
Illinois State Comptrollerillinoiscomptroller.gov
The company is responsible for managing the fiscal accounts of the state of Illinois, including ordering payments in and out |
173 |
| 50 | 172 | |
| 51 |
Housing Authority of Cook Countythehacc.org
A municipal corporation in Illinois providing affordable housing, economic opportunities, and discrimination-free living environments to residents across 108 communities |
170 |
| 52 |
Village of Tinley Parktinleypark.org
Dynamic community near Chicago with great schools, superior services, outstanding park district, and Chamber of Commerce, providing a remarkable place to live, work, and visit |
168 |
| 53 |
City of Elmhurstelmhurst.org
A suburban city committed to providing governmental services, enhancing quality of life, and offering diverse housing, shopping, dining, and cultural experiences |
165 |
| 54 |
Village of Buffalo Grovevbg.org
The Village of Buffalo Grove offers a safe, family-friendly community with high-quality education, parks, entertainment, and a thriving commercial sector |
163 |
| 55 |
City of Galesburgci.galesburg.il.us
Providing essential city services, managing local government operations, and serving as the county seat of Knox County since 1873 |
160 |
| 56 |
State Universities Retirement Systemsurs.org
This company provides benefit services to over 240,000 members worldwide, serving 61 employers in Illinois with offices in Champaign and Naperville |
157 |
| 57 |
Will County Executivewillcountyillinois.com
A growing county in the US with diverse municipalities and townships, offering business opportunities and a mix of city, suburban, and rural lifestyles |
157 |
| 58 |
Kentucky Public Pensions Authoritykyret.ky.gov
A retirement system in Kentucky providing benefits for state and county employees, including state police officers, serving over 421,000 members |
156 |
| 59 |
City of Urbana, Illinoisurbanail.gov
The company is located in Urbana, Illinois, offering a high quality of life, affordable housing, top-ranked schools, and vibrant arts and entertainment options |
155 |
| 60 |
City of Chicago Office of Inspector Generaligchicago.org
The independent City of Chicago Office of Inspector General fights corruption, waste, and mismanagement in City government to promote integrity and accountability |
150 |
| 61 |
Village of Glendale Heightsglendaleheights.org
A progressive village providing community events and programs for residents in Glendale Heights |
149 |
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More company lists in Illinois
- The largest companies in Illinois 4,175
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- IT Services and IT Consulting companies in Illinois 230
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- Critical infrastructure operators in Illinois 178
- Education providers in Illinois 176
- Retail chains in Illinois 172
- SaaS companies in Illinois 172
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- Healthcare providers in Illinois 140
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- Non-profit Organizations companies in Illinois 106
- Venture capital and private equity firms in Illinois 103
- Consulting firms in Illinois 96
The same list elsewhere in United States
- Government Administration companies in the United States 2,059
- Government Administration companies in California 279
- Government Administration companies in Florida 113
- Government Administration companies in Texas 113
- Government Administration companies in New York State 93
- Government Administration companies in Virginia 69
- Government Administration companies in North Carolina 68
- Government Administration companies in Maryland 62
- Government Administration companies in Alabama 61
- Government Administration companies in Massachusetts 61
- Government Administration companies in Washington State 60
- Government Administration companies in Ohio 54
- Government Administration companies in Minnesota 51
- Government Administration companies in Michigan 50
- Government Administration companies in Colorado 49
- Government Administration companies in Arizona 48
- Government Administration companies in Georgia 48
- Government Administration companies in Pennsylvania 48
- Government Administration companies in New Jersey 40
- Government Administration companies in Oregon 40
- Government Administration companies in Wisconsin 40
- Government Administration companies in Tennessee 34
- Government Administration companies in Washington 99
- Government Administration companies in Sacramento 42