When Does The Penalty Apply?
The late payment penalty applies when a taxpayer fails to pay the tax by the due date. For tax year 2017, the due date is April 17, 2018. To avoid penalties, payments must be made by the due date even if you file on extension.
New Rate Per Month
Beginning with tax year 2017, the rate for calculating the late payment penalty is 0.5% per month, calculated daily, on the amount of taxes past due. The maximum amount of late payment penalty that may be assessed remains 12% of the tax due as in prior years.
Automatic Waiver of Penalties
The penalty is automatically waived if a taxpayer already paid 90% of the taxes due for the tax year, or if a taxpayer pays the taxes past due within 30 days following the first notice from the department of the amount owed.
See 15-1-2016, MCA.
Learn more about Late Fees, Penalties, and Interest.