According to the Congressional Budget Office, the U.S. government spent $4.0 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.

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.

Click here to see the 30 companies getting the most from the government.