Governor Gianforte Extends Tax Filing Deadline to May 17

March 18, 2021

Governor Greg Gianforte today extended the filing and payment deadlines for 2020 Montana individual income tax returns to May 17, 2021.

Last year brought real, serious challenges to Montanans, and it’s only appropriate to extend the deadline so Montana taxpayers have some extra time to file, without having to worry about interest or penalties,” Governor Gianforte said.

The May 17 deadline is in keeping with the new federal filing deadline announced yesterday.

The Department of Revenue advises that the American Rescue Plan Act excludes the first $10,200 of unemployment benefits from federal taxes for those making less than $150,000. Those who have already filed their federal and Montana tax returns do not have to amend their returns. But those who received unemployment benefits in 2020 and have not yet filed should follow the revised instructions for their Montana return at

The Department of Revenue also reminds taxpayers:

  • It could take up to 90 days to process refunds for some taxpayers due to security measures taken against identity theft and fraud. Taxpayers can check the status of their refund at
  • Electronic filing is the safest and fastest way to file your return and get your refund as quickly as possible.
  • For those who worked remotely in Montana during any part of 2020, income earned while working in the state is taxable in Montana.
  • Any taxpayers who move after filing their Montana returns should keep their mailing address current with the department to avoid any delays in receiving their refund or correspondence from the department.

Deadlines for quarterly estimated payments of 2021 income taxes have not changed.