The budget is more than just a tally of numbers. It also expresses the policy priorities of our government. Each year, the president and Congress have the opportunity to set priorities for the federal government, determining how much to spend through appropriations for annually funded programs as well as reviewing entitlement programs and the tax code.
In 2019, total federal spending was $4.4 trillion — about one-fifth of the economy and $13,600 for each person living in the United States. In 2020, spending temporarily rose to $6.6 trillion as a result of the economic effects of the pandemic and the legislative response to mitigate them.
Spending in the federal budget can be divided into three categories: mandatory, discretionary, and interest.
Programs governed by provisions of permanent law are referred to as “mandatory.” Put another way, spending on a mandatory program is essentially on “autopilot” unless policymakers change the laws governing the program.
Many programs that provide benefits to individuals are classified as mandatory spending, such as Social Security, Medicare, and Medicaid. Those programs are also often referred to as "entitlements" because individuals who meet the programs’ eligibility requirements are "entitled" to benefits.
Mandatory spending covers programs in six major areas:
Lawmakers do not provide specific funding levels for mandatory spending. Instead, they specify who is eligible for benefits as well as the type and level of benefits that each person can receive. For example, the unemployment insurance program has eligibility criteria that, once met, entitle an individual to receive a certain level of benefits. Total spending on the program depends on the number of people who file for unemployment, not on a fixed amount of funding set by lawmakers.
The term "mandatory" doesn’t mean that lawmakers are powerless to alter this spending. Elected officials can at any time adjust the eligibility criteria and benefit formulas that determine spending on mandatory programs, as they did with Social Security in 1983. However, if Congress and the president take no action, the current formulas and criteria for benefits remain in place year after year, and the spending flows as specified by the law without interruption.
Over time, spending for mandatory programs has increased more quickly than most other programs — primarily because of growth in Social Security, Medicare, and Medicaid. In 1970, only 31 percent of the federal budget was spent on mandatory programs, while the rest funded an array of discretionary programs and net interest. CBO estimates that in 2020, 70 percent of federal spending will go to mandatory programs. Coronavirus has impacted these numbers significantly; in 2019, 61 percent of federal spending went to mandatory programs.
Discretionary spending is determined on an annual basis by Congress and the president through enactment of appropriations. As opposed to the "automatic" nature of mandatory spending, discretionary spending must be revisited each year.
There are 12 separate appropriation bills that are supposed to be annually shepherded through the Congress by the appropriations committees. Defense spending represents more than half of all discretionary spending. Other major activities funded through appropriations include homeland security, education, transportation, research, food safety, science and space programs, disaster assistance, environmental protection, public housing, and federal law enforcement.
Historically, most federal spending was discretionary. In the 1960s, two-thirds of total federal spending went to fund discretionary programs. Today, discretionary spending is about one-quarter of the budget, though this number was affected by the legislative response to the pandemic. Over the next decade, it will decrease to a historically low level relative to the size of our national economy.
The third major category of spending is interest on the national debt. Interest rates on our debt are currently low but are projected to increase. In fact, interest costs are the fastest-growing “program” in the federal budget — exceeding the growth in Social Security or Medicare. Under current law, CBO projects that net interest costs will grow from 8 percent of the budget in 2020 to 9 percent in 2030, and 26 percent in 2050. As a share of economy, that equates to 1.6 percent of gross domestic product in 2020, 2.2 percent in 2030, and 8.1 percent in 2050.