The Antideficiency Act (31 U.S.C. 1341-1342, 1511-1519) generally bars the obligation or expenditure of federal funds in the absence of appropriations. The interval during a fiscal year when appropriations for a particular project or activity are not enacted into law, either in the form of a regular appropriations act or a CR, is referred to as a funding gap or funding lapse . Although funding gaps may occur at the start of the fiscal year, they may also occur any time a CR expires and another CR (or the relevant regular appropriations bill) is not enacted immediately thereafter. Multiple funding gaps may occur within a fiscal year. It is under this guidance that exceptions may be made for activities involving "the safety of human life or the protection of property." As a consequence of these guidelines, when a funding gap occurs, executive agencies begin a shutdown of the affected projects and activities, including the furlough of non-excepted personnel. The general practice of the federal government after the shutdown has ended has been to retroactively pay furloughed employees for the time they missed, as well as employees who were required to come to work. Under current practice, although a shutdown may be the result of a funding gap, the two events should be distinguished. This is because a funding gap may result in a shutdown of all affected projects or activities in some instances but not in others. For example, when a funding gap is of a short duration, agencies may not have enough time to complete a shutdown of affected projects and activities before funding is restored. In addition, the Office of Management and Budget has previously indicated that a shutdown of agency operations within the first day of a funding gap may be postponed if it appears that an additional CR or regular appropriations act is likely to be enacted that same day. Seven of the funding gaps commenced with the beginning of the fiscal year on October 1. Funding gaps have ranged in duration from 1 to 34 full days. Between 1980 and 1990, the duration of funding gaps was generally shorter, typically ranging from one day to three days. Notably, many of the funding gaps that have occurred since FY1977 do not appear to have resulted in a "shutdown." Thus, while agencies tended to curtail some operations in response to a funding gap, they often "continued to operate during periods of expired funding." In addition, some of the funding gaps after the Civiletti opinions did not result in a completion of shutdown operations due to both a funding gap's short duration and an expectation that appropriations would soon be enacted. Some of the funding gaps during this period, however, did have a broader impact on affected government operations, even if only for a matter of hours. The chronology of regular and continuing appropriations enacted during that fiscal year is illustrated in Figure 1 . None of the 12 regular appropriations bills for FY2014 was enacted prior to the beginning of the funding gap. FY2018

At the beginning of FY2018, none of the 12 regular appropriations bills had been enacted, so the federal government operated under a series of CRs. 115-120 , on January 22. 115-298 at midnight on December 21, 2018. Because of this funding gap, federal agencies and activities funded in these seven regular appropriations bills were required to shut down. The funding gap ended when a CR, P.L. The funding gap lasted 34 full days.
The Antideficiency Act (31 U.S.C. 1341-1342, 1511-1519) generally bars the obligation of funds in the absence of appropriations. Exceptions are made under the act, including for activities involving "the safety of human life or the protection of property." The interval during the fiscal year when appropriations for a particular project or activity are not enacted into law, either in the form of a regular appropriations act or a continuing resolution (CR), is referred to as a funding gap or funding lapse. Although funding gaps may occur at the start of the fiscal year, they may also occur any time a CR expires and another CR (or the regular appropriations bill) is not enacted immediately thereafter. Multiple funding gaps may occur within a fiscal year.
When a funding gap occurs, federal agencies are generally required to begin a shutdown of the affected projects and activities, which includes the prompt furlough of non-excepted personnel. The general practice of the federal government after the shutdown has ended has been to retroactively pay furloughed employees for the time they missed, as well as employees who were required to come to work.
Although a shutdown may be the result of a funding gap, the two events should be distinguished. This is because a funding gap may result in a total shutdown of all affected projects or activities in some instances but not others. For example, when funding gaps are of a short duration, agencies may not have enough time to complete a shutdown of affected projects and activities before funding is restored. In addition, the Office of Management and Budget has previously indicated that a shutdown of agency operations within the first day of the funding gap may be postponed if a resolution appears to be imminent.
Since FY1977, 20 funding gaps occurred, ranging in duration from 1 day to 34 full days. These funding gaps are listed in Table 1. About half of these funding gaps were brief (i.e., three days or less in duration). Notably, many of the funding gaps do not appear to have resulted in a "shutdown." Prior to the issuance of the opinions in 1980 and early 1981 by then-Attorney General Benjamin Civiletti, while agencies tended to curtail some operations in response to a funding gap, they often "continued to operate during periods of expired funding." In addition, some of the funding gaps after the Civiletti opinions did not result in a completion of shutdown operations due to both the funding gap's short duration and an expectation that appropriations would soon be enacted. Some of the funding gaps during this period, however, did have a broader impact on affected government operations, even if only for a matter of hours.
Two funding gaps occurred in FY1996, amounting to 5 days and 21 days. The chronology of regular and continuing appropriations enacted during FY1996 is illustrated in Figure 1.
At the beginning of FY2014 (October 1, 2013), none of the regular appropriations bills had been enacted, so a government-wide funding gap occurred. It concluded on October 17, 2013, after lasting 16 full days.
During FY2018, there was a funding gap when a CR covering all of the regular appropriations bills expired on January 19, 2018. It concluded on January 22, 2018, after lasting two full days.
The most recent funding gap occurred during FY2019, when a CR covering federal agencies and activities funded in 7 of the 12 regular appropriations bills expired on December 21, 2018. It concluded on January 25, 2019, after lasting 34 full days.
For a general discussion of federal government shutdowns, see CRS Report RL34680, Shutdown of the Federal Government: Causes, Processes, and Effects, coordinated by Clinton T. Brass.