It's  déjà vu all over again, again - Congress seems to be ignoring the  gathering fiscal storm clouds. The most immediate of these is just  around the corner: if lawmakers do not pass legislation to fund federal  programs by September 30, the government will shut down.
What is a government shutdown?
Many  federal government agencies and programs rely on annual funding  appropriations made by Congress. Since the government's fiscal year  starts on October 1, a government shutdown will occur if Congress does  not pass appropriations bills for next fiscal year by September 30. In a  "shutdown," federal agencies must discontinue all non-essential  discretionary functions until new funding legislation is passed and  signed into law. Essential services continue to function, as do  mandatory spending programs.
What services are affected in a shutdown and how?
Each  federal agency develops its own shutdown plan, following guidance  released in previous shutdowns and coordinated by the Office of  Management and Budget (OMB). The plan identifies which government  activities may not continue until appropriations are restored, requiring  furloughs and the halting of many agency activities. However,  "essential services" - mainly those related to public safety - continue  to operate, with payments covering any obligations incurred only when  appropriations are enacted. In prior shutdowns, border protection, in  hospital medical care, air traffic control, law enforcement, and power  grid maintenance have been among the services classified as essential,  while some legislative and judicial staff have also been largely  protected. Mandatory spending not subject to annual appropriations, such  as for Social Security, Medicare and Medicaid also continues. Other  example of activities that continue are activities funded by permanent  user fees not subject to appropriations such as immigration services  funded by visa fees.
Although  a number of programs are exempt, the public is still likely to feel the  impact of a shutdown in a number of ways. For example:
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Social Security and Medicare:  Checks are sent out, but benefit verification as well as the issuance  of cards would cease. While unlikely to happen again, in 1996 
over 10,000 Medicare applicants were temporarily turned away every day of the shutdown.
 
 
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Environmental and Food Inspection:  In 2013, the Environmental Protection Agency halted site inspections to  1,200 different sites that included hazardous waste, drinking water and  chemical facilities. The FDA delayed just almost 900 inspections.
 
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National Parks:  During the 2013 shutdown, the National Park Service turned away  millions of visitors to more than 400 parks, national monuments, and  other sites. The National Park Service estimated that the shutdown led  to over half a billion dollars in lost visitor spending nationwide.
 
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Health and Human Services:  The National Institutes of Health would be prevented from admitting new  patients or processing grant applications. In 2013, states were 
forced to front the money for formula grant programs such as Temporary Assistance for Needy Families (cash welfare).
 
 
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Internal Revenue Service:  In the event of a shutdown, the IRS, which verifies income and social  security numbers, would again not be able to perform this service. In  2013, a backlog of 1.2 million such requests potentially delayed  mortgage and other loan approvals. As well billions of dollars of tax  refunds were delayed.
 
Is the government preparing for a shutdown?
The  administration has held a conference call with senior officials to  discuss agencies' preparations for a possible shutdown.  OMB 
indicated that agencies will be following similar procedures to the 2013 shutdown  with plans updated for this year.  Those updated plans have not yet  been made public like they were in 2013.
 
How would federal employees be affected?
If  agency shutdown plans are similar to those in place in 2013, the last  time there was a shutdown, approximately 850,000 of 2.1 million  non-postal federal employees would be furloughed. In 2013, most of the  350,000 civilian employees of the Department of Defense were recalled to  work within a week. Furloughed employees would not be allowed to work  and would not receive paychecks. While Congress has historically granted  back pay, it is not guaranteed.
How and why do mandatory programs continue during a shutdown?
Whereas  discretionary spending must be appropriated every year, mandatory  spending is authorized either for multi-year periods or permanently.  Thus, mandatory spending generally continues during a shutdown. However,  some services associated with mandatory programs may be diminished if  there is a discretionary component to their funding. For instance, in  both the 1996 shutdowns and the 2013 shutdown, Social Security checks  continued to go out. However, staff who handled new enrollments and  other services, such as changing addresses or handling requests for a  new Social Security card, were initially furloughed in 1996. In 
2013,  a more limited amount of activities were discontinued, including  verifying benefits and providing new and replacement cards, but  processing of benefit applications or address changes continued. At  least one major mandatory program would pause: the Supplemental  Nutrition Assistance Program (SNAP, commonly known as "food stamps").  The USDA 
indicated they would not be able to administer the program during a shutdown this  year because contingency funds that were used to administer the program  during 2013's shutdown have been exhausted.
 
How many times has the government shut down?
 Since  Congress introduced the modern budget process in 1976, there have been  18 "funding gaps," where funds were not appropriated for at least one  day. However, before 1980, the government did not shut down, but  continued normal operations through six funding gaps. Between 1981 and  1994, all nine funding gaps occurred over a weekend, and government  operations were only minimally affected.
There  have been three "true" shutdowns. The first two happened in the winter  of 1995-1996, when President Bill Clinton and the Republican Congress  were unable to agree on spending levels and shut down the government  twice for a total of 26 days. The third was in 2013 when the House and  Senate standoff on funding resulted in a 16-day shutdown.
Does a government shutdown save money?
While  estimates vary widely, evidence suggests that shutdowns tend to cost,  not save, money. For one, putting contingency plans in place has a real  cost. In addition, a number of user fees and other charges are not  collected during a shutdown. Contractors sometimes include premiums in  their bids to account for uncertainty in being paid. And although many  federal employees are forced to be idle during a shutdown, they have  historically received back pay, negating much of those potential  savings. OMB 
official estimates of the 2013 government shutdown found that $2.5 billion in pay and  benefits was paid to furloughed employees for hours not worked during  the shutdown as well as roughly $10 million in penalty interest payments  and lost fee collections.
 
How can Congress avoid a shutdown?
There  are essentially two ways to avoid a government shutdown - by passing  appropriations or a continuing resolution (see below question on "What  is a Continuing Resolution?"). Theoretically, the House and Senate  Appropriations committees are supposed to pass 12 different  appropriations bills, broken up by subject area and based on funding  levels allocated in a budget resolution. Often, these bills are combined  into a larger "omnibus" or "minibus" set of appropriations.
This  year, no appropriations bill has been passed by both chambers. The  House Appropriations Committee has passed all twelve bills, but only six  - Defense, Military Construction-VA, Energy-Water, Homeland Security,  Commerce-Justice-Science, and Legislative - have made it through the  full House of Representatives. Meanwhile, the Senate Appropriations  Committee has passed all bills, but the full Senate has not passed any  of them.
What is a Continuing Resolution (CR)?
A  continuing resolution temporarily funds the government in the absence  of full appropriations bills, often by continuing funding levels from  the prior year. Traditionally, CRs have been used to give lawmakers a  short period of time to complete their work on remaining appropriations  bills while keeping the government operating. CRs sometimes apply to  only a few categories of spending, but can also be used to fund all  discretionary functions, and can be used for an entire year.
CRs  differ from normal appropriations bills in that they often "continue"  the funding allocations from previous bills at the prior year's rate or a  formula based on the prior year's rate. Even when overall funding  levels have differed, lawmakers have often simply scaled up all accounts  by a percent change in spending rather than making individual decisions  on spending accounts. However, CRs often do include certain  "anomalies," where specific items are increased or decreased to work  around some problems that would occur from continuing the previous  year's policies, or "policy riders," specifying certain statements of  policy.  Colloquially, a "clean CR" does not contain policy riders or  politically motivated changes to funding levels.
How often does Congress pass CRs?
Congress  frequently passes CRs when it is unable to agree on appropriations, and  occasionally multiple CRs are necessary to fund the government for an  entire fiscal year. They have also sometimes been relied on during  Presidential transition years. In FY 2001, for instance, a series of  intense congressional negotiations leading up to the 2000 elections led  to a series of ten one-day CRs. In total, Congress funded the first  three months of that fiscal year with 21 continuing resolutions.
Not  surprisingly, CRs have been quite prevalent in the past few years,  being used to fund the government entirely in FY 2011, when eight CRs  were passed; in FY 2013, when two CRs were passed; and in FY 2014, when  two CRs after the government shutdown bought time before final passage  of the Ryan-Murray agreement. Even the less-contentious FY 2015 funding  negotiations necessitated three CRs before passage of the 
CROmnibus appropriations bill, which still contained a CR for Homeland Security.  The most recent year when a full-year appropriations bill passed and no  CRs were necessary was 1997.
 
What are the disadvantages of using CRs? 
Continuing  resolutions have several negative implications on the budget's overall  efficiency. CRs usually continue funding at the past year's level  without any regard for changing policy needs or the value of each  program within an agency. Using a continuing resolution wastes hundreds  of hours of careful consideration and program evaluation incorporated  into each agency's budget submission. For instance, the President's  budget annually proposes a list of eliminations and reductions of  programs that are duplicative or ineffective; a continuing resolution  will continue to fund these unwanted programs. Finally, the use of  continuing resolutions disrupts activities within agencies, makes it  difficult to plan or start future projects, and costs staff time to  revise work plans every time the budget changes.
How is the House addressing funding?
As  of September 24, the House has debated and passed a bill that would  defund Planned Parenthood, which press reports suggest is demanded by  many conservatives to be a part of any government funding bills. The  House has not voted on a CR. No official bills nor time frame for votes  are available at this time. The White House has threatened to veto the  bill that defunds Planned Parenthood.
How is the Senate addressing funding?
As  of September 24, the text of a short-term CR (funding the government  through December 11th) has been released with cloture votes scheduled,  but it includes language defunding Planned Parenthood. Press reports  suggest that specific language will not be able to get the 60 votes  necessary to advance the bill and a regular CR will then likely be voted  on extending government funding until mid-December.
How does a shutdown differ from a default? 
In  a shutdown, the government temporarily stops paying employees and  contractors who perform government services, whereas in a default the  list of parties not paid is much broader. In a default, the government  exceeds the statutory debt limit and is unable to pay some of its  creditors (or other obligations). Without enough money to pay its bills,  any of its payments are at risk?including all government spending,  mandatory payments, interest on our debts, and payments to U.S.  bondholders. While a government shutdown would be disruptive, a  government default could be disastrous.
How does a shutdown differ from "sequester"? 
A  government shutdown closes down non-essential government operations due  to lack of funding, whereas sequester or sequestration is shorthand for  the reductions in discretionary spending caps in place that constrain  the total amount of funding for annually-appropriated programs.
The  first example of sequestration was included in the  Gramm-Rudman-Hollings Balanced Budget and Emergency Deficit Control Act  of 1985. The current version of sequestration is a product of the Budget  Control Act (BCA) that resolved the 2011 debt ceiling negotiations. The  BCA called on a Joint Select Committee on Deficit Reduction (the "Super  Committee") to identify at least $1.5 trillion in deficit reduction  over ten years, and set in motion the sequester if it did not identify  at least $1.2 trillion. The Ryan-Murray Bipartisan Budget act negotiated  around some of the sequester caps for FY 2014 and 2015; however, that  agreement ends on October 1 and the full sequester-level caps return. FY  2016 appropriations, which are being negotiated at the moment, need to  be at or under those caps if they are not changed.  If appropriations  bills violate those caps, then across-the-board cuts are enforced in  January. CRFB has released a separate plan to deal with the sequester  caps called the 
Sequester Offset Solutions (SOS) plan.