The American Bankers Association has a list of more than 100 banks offering special help to furloughed workers, but each institution’s offer is different. SunTrust is offering a loan with no interest or payments for 90 days. Alpine Bank in Colorado is offering a no-interest loan up to $8,500 with no payments due until six months after the shutdown ends. Others, like US Bank and USAA, are offering low-rate loans.

Credit unions are typically more generous: Navy Federal Credit Union, for example, will allow workers who have direct deposit to take interest-free loans of up to $6,000 that will be automatically repaid when the shutdown ends. But that offer is open only to existing members who have already set up direct deposit.

The idea of a loan is hard to swallow for some employees. Interest or no, it is an obligation they would take on while uncertain when they could pay it back.

“A loan, even a zero-interest loan, is taking on additional debt based on a hope that someday the furlough will end,” said Moses Milazzo, a furloughed employee of the United States Geological Survey whose wife is also a federal employee. “What good is a loan going to do us if we can’t make the first payment next month because we are still not receiving a paycheck?”

Some workers said they worried that back pay would not be included in their eventual paychecks, despite Mr. Ross’s assurances.

“One or the both of us has been affected by every furlough since the 1995-1996 furloughs,” Mr. Milazzo said. “This is the first time we’ve been uncertain that the government will live up to its promise of offering stability and reliability.”

Mr. Pfeifer, who wanted to be clear that he was not speaking on behalf of the Forest Service, moved with his wife this month across the state of Washington, from Walla Walla to Republic. They immediately faced new expenses while still paying down credit card debt: His wife needed to buy school supplies before starting a new teaching job, and her car needed winter tires for the mountain town’s heavy snows.