Samuel Stebbins and Michael B. Sauter

24/7 Wall Street

According to the Congressional Budget Office, the U.S. government spent $4 trillion in 2017. While the budget's largest portions go toward benefit programs like Social Security and Medicaid, hundreds of billions of federal dollars also end up in the coffers of just a handful of companies in the private sector.

Through its various agencies and departments, the federal government has millions of contractual obligations with private companies, both domestic and foreign. The companies and organizations benefiting from federal dollars run the gamut from drug makers to universities and research companies. Those benefiting the most, however, are almost exclusively health care providers and defense contractors – many of which claim the U.S. government as their biggest customer.

24/7 Wall St. reviewed contract data from the Federal Procurement Data System to identify the companies making the most from the federal government. The government paid 30 companies at least $2.3 billion each in fiscal 2017. Four companies on this list were each awarded federal contracts worth over $14 billion – more than the entire budget for the Environmental Protection Agency or the Department of the Interior.

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In addition to defense contractors, health insurance companies make up a considerable portion of this list. As the single largest employer in the country, the federal government provides jobs with benefits to millions of people, not including the many veterans and their families for whom the government is obligated to provide insurance.

To identify the companies gaining the most from the federal government, 24/7 Wall St. reviewed data compiled by the General Services Administration and accessed through the Federal Procurement Data System. Companies were based on total payments received from U.S. government contract obligations in the 2017 government fiscal year. Data on individual contracts also came from the Federal Procurement System. Corporate revenues came from publicly available financial documents when available and are for the most recent fiscal year, which does not necessarily align with the federal government’s fiscal year.

30. California Institute Of Technology

• Contracts won in 2017: $2.4 billion

• Largest federal agency customer(s): NASA

• Revenue: N/A

CalTech is the largest recipient of NASA contracts in the United States. The school received a total of $2.4 billion from NASA in 2017. Much of those contract funds go to the Jet Propulsion Laboratory, a center located near the university campus that carries out robotic exploration of space. Among the JPL’s spacecraft are the Curiosity rover, which landed on Mars in 2012, the Juno spacecraft currently orbiting Jupiter, and the NuSTAR X-ray space black hole telescope.

29. Honeywell International Inc.

• Contracts won in 2017: $2.4 billion

• Largest federal agency customer(s): Energy, DoD

• Revenue: $41.8 billion

Industrial conglomerate Honeywell International won $2.4 billion in federal government contracts in 2017. Still, government dollars account for a relatively small share of the company's overall revenue. Honeywell reported $41.8 billion in revenue in its most recent fiscal year, nearly 18 times more than the value of its government contracts in 2016.

The majority of the companies making the most from the government are defense contractors, and much of Honeywell's business is also in defense. Two of the company's three largest buyers in the government are the Department of Defense and the U.S. Army. The company's products include avionics and cockpit electronic equipment, navigation tools, engines, and sensors.

28. CACI International Inc

• Contracts won in 2017: $2.4 billion

• Largest federal agency customer(s): DoD, Army

• Revenue: $4.5 billion

Information technology giant CACI won the largest contract in its more than 50 year history in fiscal 2017. The five-year, $1.77 billion contract will fund work on the federal government's Joint Improvised-Threat Defeat Organization, a program that develops technology aimed at countering car bombs, roadside bombs, and other improvised explosives.

The work has been instrumental in Iraq, where CACI has provided a range of information technology and intelligence services for over a decade. Since the United States entered Iraq in 2003, CACI has largely grown through a combination of acquisitions and increased contract work. CACI reported $4.5 billion in revenue in fiscal 2018, more than five times the revenue reported in 2003.

27. TriWest Healthcare Alliance Corp.

• Contracts won in 2017: $2.4 billion

• Largest federal agency customer(s): Veterans Affairs

• Revenue: N/A

While most of the companies on this list are military contractors, several are health insurance providers, including TriWest Healthcare Alliance Corp. The company in 2018 was given sole control of the Department of Veterans Affairs primary community care programs. For the previous five years, TriWest had been jointly managing the VA's two main outpatient care programs with Health Net Federal Services.

26. United Technologies Corporation

• Contracts won in 2017: $2.5 billion

• Largest federal agency customer(s): DoD, Air Force

• Revenue: $66.5 billion

United Technologies Corporation was awarded over 150,000 government contracts since 2007 from departments such as the Department of Defense, National Aeronautics and Space Administration, and State Department. In 2018, the company announced plans to split into three separate companies to better specialize in each specific business. Much of UTC's government business is related to aerospace products, developed by subsidiary brand Pratt & Whitney. The company manufactures jet engines for fighter and transport aircraft for the U.S. and 28 other militaries around the world.

25. Los Alamos National Security LLC

• Contracts won in 2017: $2.5 billion

• Largest federal agency customer(s): Energy

• Revenue: $5.3 billion

The Los Alamos National Laboratory's current stated mission is to "focus on national security and contributions to 21st century science." The lab was originally created to develop the atomic bomb during World War II.

Earlier this year, nonprofit Triad National Security LLC took over management of the lab. Despite its nonprofit status, New Mexico lawmakers are fighting to ensure the company will continue to pay state taxes. Today, about 65 percent of the laboratory's budget goes towards weapons development.

24. General Electric Company

• Contracts won in 2017: $2.5 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $121.6 billion

General Electric was taken off the Dow Jones Industrial Average index of stocks last year after poor performance in the market. One spot of bright news for the historical American company was the increase in GE's total awarded federal contracts value from $1.9 billion in 2016 to $2.5 billion in fiscal year 2017. In 2018, the company was awarded a $631 million contract with the Department of Defense to repair fighter jet engines.

23. Bell Boeing Joint Project Office

• Contracts won in 2017: $2.5 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $101.1 billion

The Bell and Boeing joint company has been receiving government contracts since both companies were awarded in 1983 a contract to jointly develop the V-22 Osprey combat aircraft. The partnership between Boeing and Bell Helicopter exists solely to develop and produce the aircraft. In 2017, the company received $2.5 billion in government contracts. In early 2018, Bell and Boeing won a $23.3 million federal contract from the U.S. Naval Air Systems Command to continue working on the aircraft.

22. National Technology & Engineering Solutions of Sandia LLC

• Contracts won in 2017: $2.5 billion

• Largest federal agency customer(s): Department of Energy

• Revenue: $41.8 billion

In 2017, National Technology & Engineering Solutions Of Sandia LLC, a subsidiary of defense contractor Honeywell (also on this list), took over management of Sandia National Laboratories, which is part of the national nuclear weapons program. The contract, worth $12.7 billion in total, is for a term of five years, or $2.5 billion per year.

21. Alliant Techsystems Inc.

• Contracts won in 2017: $2.5 billion

• Largest federal agency customer(s): DoD, NASA

• Revenue: $4.8 billion

Like most companies on this list, Alliant is a defense contractor, and the Defense Department accounts for more of the company's revenue than any other government agency. The company manufactures and sells a range of large, medium, and small caliber ammunition, in addition to propulsion systems for air, land, and sea-based missiles and missile defense systems. In addition to munitions systems, the company also produces spacecraft and spacecraft components and has contracts with NASA to deliver cargo to the International Space Station.

20. Centene Corporation

• Contracts won in 2017: $2.6 billion

• Largest federal agency customer(s): DoD, Defense Health Agency

• Revenue: $60.1 billion

The federal government awarded Centene Corporation $2.6 billion in contracts in 2017 to provide health insurance for public sector employees. This contract represents a relatively small part of the company's $60 billion in annual revenue. Like other health care companies on this list, Centene is a large, publicly-traded health care management company. In 2016, Health Net Federal Services, one of the primary health contractors for the Department of Defense, became a subsidiary of Centene.

19. General Atomic Technologies Corporation

• Contracts won in 2017: $2.7 billion

• Largest federal agency customer(s): DoD, Air Force

• Revenue: N/A

General Atomic Technologies Corporation, founded in 1955 as a subsidiary of General Dynamics, is one of the companies receiving the most money from the government. The company, which has contracts with the Department of Defense and the Air Force is one of the leading producers of unmanned aerial vehicles (drones). It also develops aircraft launch and recovery systems, missile defense, and space systems.

18. CSRA Inc.

• Contracts won in 2017: $2.9 billion

• Largest federal agency customer(s): Homeland Security, DoD

• Revenue: $5.0 billion

CSRA Inc. was awarded nearly $3 billion in federal government contracts in fiscal 2017. In 2018, the company was purchased by defense contractor juggernaut General Dynamics for $9.7 billion. As an independent company, CSRA provided IT solutions for a variety of government bodies, including the Department of Homeland Security. It appears the former parts of CSRA will continue to do so as part of General Dynamics' operations.

17. UnitedHealth Group Incorporated

• Contracts won in 2017: $3.0 billion

• Largest federal agency customer(s): Defense Health Agency, DoD

• Revenue: $226.2 billion

UnitedHealth Group is a private health care company that offers health benefit plans for government workers, individuals, and small- and mid-size businesses. The government awarded UnitedHealth $3.0 billion worth of contracts in fiscal year 2017. All told, the health care giant serves 126 million people, including those in government agencies across 36 states and Washington, D.C.

16. Harris Corporation

• Contracts won in 2017: $3.2 billion

• Largest federal agency customer(s): DoD, Army

• Revenue: $6.2 billion

The majority of defense contractor Harris Corporation's annual revenue comes from government contracts. The company's segments include an electronic warfare systems division and a communication systems division, which manufactures night vision and other networked and integrated communication products. Standing contracts with the government include lucrative deals with the U.S. Army, Air Force, and Special Operations Forces. In addition to the U.S. government, the company has clients in over 100 countries.

15. Science Applications International Corporation

• Contracts won in 2017: $3.5 billion

• Largest federal agency customer(s): DoD, Army

• Revenue: $4.5 billion

Science Applications International Corporation provides technical, engineering, and IT services primarily to the U.S. government. The vast majority of the company's total revenues came from the government in fiscals 2017, 2016, and 2015. The company works with state governments in addition to the federal government. In 2017, the company signed a $165 million contract with the state of Virginia to aid the Virginia Information Technologies Agency with modernizing its technology infrastructure.

14. Humana Inc.

• Contracts won in 2017: $3.7 billion

• Largest federal agency customer(s): DoD, Defense Health Agency

• Revenue: $56.9 billion

Health insurance company Humana offers a number of insurance products, including supplemental Medicare plans. Much of the company's $3.7 billion in federal contracts in fiscal 2017 came from those Medicare plans. The company covers the East and South regions of Tricare, the health care program of the U.S. Department of Defense. Humana has been working with the DoD since 1996.

13. Booz Allen Hamilton Holding Corporation

• Contracts won in 2017: $4.1 billion

• Largest federal agency customer(s): DoD, GSA

• Revenue: $6.2 billion

Booz Allen Hamilton is a consulting firm, and though it has clients in the private sector, the majority of its revenue comes from government contracts. Working with several U.S. intelligence agencies, including the National Security Agency and the Department of Homeland Security, and branches of the U.S. military, much of the company's business is confidential. It is not likely a coincidence that 70 percent of company employees have security clearance. Generally, Booz Allen Hamilton provides intelligence and data analysis, engineering, and cybersecurity services to government clients.

12. AECOM

• Contracts won in 2017: $4.1 billion

• Largest federal agency customer(s): Energy, DoD

• Revenue: $20.2 billion

One of the largest design companies in the world, AECOM provides a range of planning, consulting, construction, and management services to public and private clients. It has been responsible for such major projects as the masterplan for the 2016 Rio Olympic Games, management services for Chicago's Millennium Park, and construction on both the original Twin Towers in 1973 and One World Trade Center 30 years later, as well as 9/11 cleanup efforts.

The federal government is AECOM's largest customer. The government awarded the company over $4 billion in contracts in 2017. Within the federal government, AECOM's largest client is the Department of Energy, for which the company largely provides nuclear decontamination and decommissioning services.

11. Leidos Holdings Inc.

• Contracts won in 2017: $4.8 billion

• Largest federal agency customer(s): DoD, Health & Human Resources

• Revenue: $10.2 billion

Leidos Holding is a science, engineering, and technology company. Its work includes the development of national security solutions for the U.S. Department of Defense, the U.S. Intelligence Community, and the U.S. Department of Homeland Security among others. For fiscal year 2017, 84 percent of the company's total revenues came from the U.S. government, an increase from fiscal 2016's 81 percent. In 2016, Lockheed Martin separated its information systems and global solutions business segment and merged it with Leidos, effectively making Leidos the largest IT provider working for the federal government.

10. L3 Technologies Inc.

• Contracts won in 2017: $5.2 billion

• Largest federal agency customer(s): DoD, Air Force

• Revenue: $10.2 billion

L3 Technologies is a company that provides intelligence, surveillance, and reconnaissance products and services for land, sea, and space missions for a variety of government and commercial customers. The company was awarded $5.2 billion in contracts with the federal government in 2017. One of the contracts was a $37.6 million maintenance deal to provide support to the Navy's T-45 Goshawk aircraft system.

9. BAE Systems Plc

• Contracts won in 2017: $5.3 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $23.8 billion

BAE Systems was awarded more in U.S. government contracts in 2017 than any other company based in a foreign country. The U.K.-based company made $5.3 billion in 2017 in U.S. taxpayer dollars. A major defense contractor, BAE Systems designs and manufactures fighter jets, artillery systems, electronic equipment, and surface combat vehicles. Nearly a third of BAE's 83,200 employees are based in the United States.

8. Bechtel Group Inc.

• Contracts won in 2017: $5.5 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: N/A

Bechtel Group is a private engineering, construction, and project management company. With $5.5 billion in contracts from the federal government in 2017 -- largely from deals with the Defense Department and Navy -- it is also one of the largest defense contractors in the world. The company has worked with the U.S. government, and many of its allies, providing missile defense services and developing and maintaining military bases and other infrastructure for over 50 years. The company's recent projects with the U.S. government include a missile defense and space surveillance program at the Ronald Reagan Ballistic Missile Test Site in the Marshall Islands.

7. Huntington Ingalls Industries Inc.

• Contracts won in 2017: $7.2 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $8.2 billion

One of the largest defense contractors in the world, Huntington Ingalls Industries won $7.2 billion in federal contracts in 2017. The only company in the world to build U.S. aircraft carriers and one of just two to build nuclear-powered submarines, Huntington Ingalls is critical to the strength of the U.S. Navy. Some of the company's recent government deals include a $60 million contract to overhaul the USS Boise, a light cruiser vessel, and a $468 million contract to begin component development for the U.S. Navy's Columbia-class submarine, a nuclear sub slated for use in 2021.

6. Mckesson Corporation

• Contracts won in 2017: $8.8 billion

• Largest federal agency customer(s): Veterans Affairs, DoD

• Revenue: $208.4 billion

McKesson Corporation is one of several health care companies to receive billions of dollars from U.S. taxpayers. Through its subsidiaries, the company supplies a range of branded and generic pharmaceuticals, surgical supplies, and electronic infrastructure to health care providers. The Department of Veterans Affairs is one of the company's largest clients, and the company was awarded $8.8 billion in government contracts in 2017.

5. Northrop Grumman Corporation

• Contracts won in 2017: $11.2 billion

• Largest federal agency customer(s): DoD, Air Force

• Revenue: $30.1 billion

Northrop Grumman is one of several companies on this list that are indispensable to American military might. The company manufactures and services the iconic B-2 Spirit Stealth Bomber, which the U.S. military has deployed in Iraq, Afghanistan, and most recently in Libya. Adjusted for inflation, a single B-2 bomber costs over $2 billion, and the U.S. Air Force currently has 20 in operation. The company's other business segments include drone manufacturing, cyber security, and logistics. Northrop Grumman was awarded $11.2 billion in federal government in 2017 alone.

4. Raytheon Company

• Contracts won in 2017: $14.7 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $27.1 billion

Raytheon Company is a U.S. defense contractor that manufactures weapons and electronics, including guided missiles, among other services. In recent years, Raytheon has also been contracted to aid in cyber defense and awarded a $1 billion contract with the Department of Homeland Security. In 2017 alone, the Waltham, Massachusetts-based company was awarded $14.7 billion in federal contracts.

3. General Dynamics Corporation

• Contracts won in 2017: $15.3 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $36.2 billion

General Dynamics Corporation is a Virginia-based defense contractor. The company was awarded $15.3 billion in government contracts in 2017 -- more than all but two other companies, which also happen to be defense contractors. Like several other companies on this list, General Dynamics does most of its business with the U.S. government. Sales to the federal government accounted for 85 percent of the company's revenue in 2017 and 84 percent in 2016.

2. The Boeing Company

• Contracts won in 2017: $23.4 billion

• Largest federal agency customer(s): DoD, Air Force

• Revenue: $101.1 billion

Boeing is the world's largest aerospace company and one of the largest American companies by revenue. While the company may be most well known for its commercial airplanes, it also has a large defense, space, and security segment, which lists the U.S. Department of Defense as its primary customer. Boeing's government customers include all of the branches of the U.S. military, NASA, the Federal Aviation Administration (FAA), and the Department of Homeland Security.

1. Lockheed Martin Corporation

• Contracts won in 2017: $50.7 billion

• Largest federal agency customer(s): DoD, Navy

• Revenue: $53.8 billion

The largest defense contractor in the world, Lockheed Martin made more from contracts with the federal government in 2017 than any other company. Lockheed Martin's business segments include missile defense, radar, naval warfare technology, fighter jets and intercontinental ballistic missiles. Recently, the company inked a 60-year deal for the F-35 Joint Strike Fighter jet, valued at an estimated $1 trillion -- the most expensive weapons deal in Defense Department history. The F-35 is one of the newer additions to the company's lineup, which includes the F-22 Raptor and F-16 fighter jets, the C-130 Hercules.

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