The government may have halted, but Americans still have to file taxes.

If your U.S. client requested a federal tax filing extension, the deadline is still October 15. So says the IRS Contingency Plan released last week.

Read: Don’t forget obscure U.S. tax deadlines

The plan, which only covers a five-day government shutdown, estimates the IRS still requires 9.3% of its staff to operate essential services, as well as half a day to stop remaining services.

The two largest departments that will stay open are the Criminal Investigation arm and Submission Processing Centers.

If the shutdown lasts longer than five days, the deputy commissioner for operations support will reassess the number of required staff.

Also read:

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