Tax season could have some complications this year, between the prospect of a government shutdown and the 2017 data breach at credit reporting agency Equifax EFX, -2.03% .

A partial government shutdown may happen for the first time since 2013 if Republicans and Democrats cannot agree on part of a bill related to the Deferred Action for Childhood Arrivals Program (DACA). If the bill does not pass before Saturday morning, some government agencies, including the Social Security Administration and Internal Revenue Service, could “furlough” or temporarily put on leave, some of their employees.

During the shutdown in 2013, which lasted 16 days, more than 90% of IRS workers were furloughed, which resulted in delaying some $2.2 billion in refunds to individual taxpayers.

A delayed refund can be tough for consumers, especially those who are relying on the money to pay holiday shopping debt and other expenses, said Mark Steber, chief tax officer at preparation company Jackson Hewitt.

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Given that millions of Americans have few savings and already live paycheck to paycheck, “to delay that money even a day or a few days can have catastrophic impact,” he said.

Low-income taxpayers may get hit the hardest

A government shutdown could further delay refunds that already take longer to distribute, including the Earned Income Tax Credit — a credit for low-income taxpayers — which by law cannot be refunded until mid-February, he said.

But if there’s a shutdown, that doesn’t mean you should put off filing your taxes early, he said.

The breach at Equifax in 2017 means it’s more important than ever to file early this year, before fraudsters attempt to do so on taxpayers’ behalf, in hopes of stealing their refunds.

The Federal Trade Commission warned consumers last year to file their taxes early — “as soon as you have the tax information you need, before a scammer can.”