Thousands of furloughed federal employees filed for state unemployment benefits during the weeks they were stranded without a paycheck.
But now that Congress has approved back pay for them, the states want that money back.
According to separate data obtained by CNNMoney, federal workers filed a total of 20,000 claims in Maryland, 16,000 claims in Washington D.C., 7,600 claims in Pennsylvania and around 6,000 in Virginia during the entire 16-day shutdown. Even though the shutdown has ended, more claims could still be processed in the next few days.
It's unclear just how much money was overpaid.
In Washington DC, 1,700 payments went out, totaling around $500,000. The DC Department of Employment Services had thousands more payments in the pipeline but has since instructed the bank to cancel the transactions.
The agency is also in the process of informing recipients of the repayment process.
"If they have not actually taken any money out, we will then send them a notice and reverse the payment," said Lisa Mallory, director of the agency. "If they have accessed the funds already, we will tell them the amount that needs to be repaid."
Those who already used the benefits will have 60 days to repay the DES, without interest. Workers who are in financial hardship can also apply to be part of a longer repayment plan.
If all else fails, the agency also has the authority to garnish federal workers' wages.
Some states were able to avoid the overpayment problem through sheer luck and good timing.
Pennsylvania usually has a waiting period before it sends out unemployment benefits, and in this case, funds were approved but weren't set to be dispersed until October 25. Now that the shutdown has ended, the state won't pay out the claims to federal workers.
"We think we did it just right. And because the shutdown ended, we have no overpayments due," said Sara Goulet, press secretary for the Pennsylvania Department of Labor and Industry.
The Virginia Employment Commission also said its payouts were minimal due to good timing.
This isn't the first time furloughed workers had to return their unemployment checks. During the government shutdown in 1995 and 1996, state agencies also tried to recoup the overpaid funds.