Explained | US government shutdown: What would close, what would stay open?

The funding expires on March 1 for the agencies that oversee agriculture, transportation, housing and veterans' services, among other areas.

Significant swaths of the US government would have to suspend operations as soon as March 1 if Congress does not pass spending legislation that would avert a shutdown.

Here is a guide to what would stay open and what would close if Congress failed to act, according to agency shutdown plans:

When would the government shut down?

Congress has extended government funding on a temporary basis since the fiscal year started on October 1, to buy time for Republican-controlled House of Representatives and the Democratic-controlled Senate to pass the detailed spending bills that keep government agencies running.

Funding is due to run out on March 1 for some federal agencies, including the Department of Transportation, while others like the Defense Department face a March 8 deadline.

If lawmakers do not reach a deal, many government services would shut down and hundreds of thousands of federal employees would be ordered not to work.

Other employees who provide services deemed "essential," like benefits payments and border protection, would have to continue working without pay.

March 1: Transportation, Housing, Food Safety

Funding expires on this date for agencies that oversee agriculture, transportation, housing and veterans' services, among other areas.

Airport security screeners and air-traffic control workers would be required to work. But training for 1,000 new air-traffic controllers would stop, leaving the system understaffed. The Transportation Security Administration would not be able to hire new screeners.

Food-safety inspections by the Food and Drug Administration could be delayed, but reviews of new drugs and medical devices would continue.

The Commodity Futures Trading Commission would cease most oversight activity of derivatives markets.

Monthly subsidies for public housing and low-income housing aid would be at risk. But the Federal Housing Administration would continue to back insured mortgages, and Ginnie Mae would continue to back the secondary mortgage market.

Meat and egg inspections would continue, but some lab services would be disrupted, making it harder to fight animal diseases. Crop insurance would not be affected, but some loan programs could be. Research, conservation and rural development programs would be shut down.

Benefits and medical care provided by the Department of Veterans Affairs would continue, and the Army Corps of Engineers would continue to maintain the nation's waterways.

The Department of Energy's National Nuclear Security Administration would continue maintaining nuclear weapons.

Funding for military construction projects, such as housing and other facilities, would expire. Payments to companies doing that work could be disrupted.

Contracts awarded before the shutdown would continue, but new contracts, including renewals or extensions, would not be awarded.

March 8: Military, national parks, science

Military personnel would remain at their posts, but roughly half of the Pentagon's 8,00,000 civilian employees would be ordered not to work.

Agents at federal law enforcement agencies like the FBI would remain on the job.

Most Border Patrol and immigration enforcement agents would continue to work, but local governments would not get new aid to shelter migrants.

National parks would be closed, though it would be impossible to keep visitors out of many of them.

Federal courts could operate for some time but eventually would have to scale back activity. The Supreme Court would stay open.

Criminal prosecutions, including the two federal cases against former President Donald Trump, would continue. Most civil litigation would be postponed.

US embassies and consulates would remain open, but some foreign aid programs could run out of money.

Lawmakers in Congress would continue to collect paychecks, though their staffers would not. Many White House employees would be furloughed, but President Joe Biden would continue to draw a paycheck.

Scientific research would be disrupted as agencies like the National Institutes of Health would furlough most of their workers.

Weather forecasts and fisheries regulation would continue, as would patent and trademark reviews.

The Centers for Disease Control and Prevention (CDC) would continue to monitor disease outbreaks, though other public health activities could suffer.

Most inspections of hazardous waste sites, drinking water and chemical facilities would stop. Workplace safety inspections would also be limited.

The Securities and Exchange Commission would suspend most activities.

Publication of economic data, like employment and inflation reports, would be suspended.

The Internal Revenue Service would stop examining and auditing tax returns and responding to taxpayer queries, but automated tax collection would continue.

According to the White House, 10,000 children from low-income families would lose access to the Head Start preschool program.

Unaffected services

Some government services will continue unaffected because they do not rely on Congress to fund their operations.

The US Postal Service would continue to deliver mail.

Social Security retirement and disability benefits would continue to be paid, as would food benefits through the Supplemental Nutrition Assistance Program.

The Medicare and Medicaid healthcare programs would not be affected.

The Federal Reserve, the Federal Deposit Insurance Corporation and the Office of the Comptroller of the Currency would continue to oversee banks.

The Treasury Department would continue to issue debt.