Partial government shutdown or no partial government shutdown -- the IRS expects anyone who got an extension this year to file their return by Oct. 15.
The IRS earlier this week sent out a reminder that the Oct. 15 deadline "remains in effect" for those who got a six-month extension earlier this year.
"The current lapse in federal appropriations does not affect the federal tax law, and all taxpayers should continue to meet their tax obligations as normal," the IRS said. "Individuals and businesses should keep filing their tax returns and making deposits with the IRS, as required by law."
The agency said "many" of the more than 12 million people who requested the extension have not yet filed. Some groups can still get more time, including military members.
Though taxpayers are still expected to hand in their returns by Oct. 15, the agency earlier announced that due to the partial shutdown, it will not issue any tax refunds until the government resumes normal operations.
IRS call centers also will not be staffed, though automated ones are still running.
The agency did issue a temporary reprieve to taxpayers who are getting audited. Audits will also be suspended until the government starts back up.
The Associated Press contributed to this report.