Workers going unpaid during the shutdown owe $438 million in rent and mortgage payments this month

The partial U.S. government shutdown has continued longer than any in U.S. history and left many federal workers without a paycheck. But rent and mortgage payments are still due.

A whopping 800,000 workers aren't being paid, including 380,000 who are furloughed and 420,000 who are working without salary, according to a recent report from real-estate website Zillow. Of the workers who own a home, their total mortgage payments add up to $249 million per month. Of those who rent, their payments come to $189 million.

That's a grand total of $438 million workers owe for housing just in January.

Paying those bills could be a challenge. "Like Americans in the private sector, many federal employees rely on each and every paycheck to cover critical expenses, including housing," Zillow senior economist Aaron Terrazas says in the report. Indeed, some affected employees have been making that point on Twitter.

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"Housing affordability is already stretched" in many parts of the country, Terrazas says, particularly in notoriously pricey places like San Francisco, where the median rent is $4,500 and the median home could cost you more than $1.2 million. So "a single missed payment can begin the long process toward foreclosure or eviction — which has long-term impacts on an individual's finances and economic prospects."

Already, nearly 80 percent of U.S. workers say they live paycheck to paycheck, according to a 2017 report by employment site CareerBuilder, including about 10 percent of those making $100,000 a year or more.

And 61 percent of U.S. adults don't have enough money to cover six months' worth of expenses in case of an emergency, according to a 2017 survey from financial site GOBankingRates.

Though rent and mortgage payments could raise serious issues for unpaid workers during the shutdown, Zillow reports, pending and outstanding home loans for ordinary Americans could be in jeopardy, too, especially those that need to be insured or endorsed by the Federal Housing Administration.

Like many government agencies, the FHA is "operating with limited staff and warns that endorsement of loans may be delayed," the site reports. That could affect "as many as 39,000 mortgages," the site estimates, noting that "many lower-income and/or first-time buyers opt for the FHA-insured loans because they often allow for smaller down payments and offer more forgiving credit-score requirements than conventional loans."

The Department of Housing and Urban Development told Zillow that, "with each day the shutdown continues, we can expect an increase in the impacts on potential homeowners, home sellers and the entire housing market."

President Donald Trump warned that the shutdown could continue for "months or even years" until he receives $5 billion in funding for his proposed border wall.

As long as it goes on, the shutdown could continue to have ripple effects on housing, Terrazas says: "It could have a significant impact on the housing market if it continues to drag on and furloughed workers who are would-be buyers get cold feet in the absence of paychecks.

"Buying a home is a huge leap of faith for many, as they bet on continued job security and steady income to finance their home, and consumer confidence is paramount."

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