Late payment penalty

The penalty under § 685(a)(2) is ½ (0.5) of 1% (0.01) of the unpaid tax for each month (or part of a month) the payment is late. This penalty cannot exceed 25% (0.25) of the tax paid late.

Interaction of late filing and late payment penalties – The late filing penalty will be reduced by ½% (0.005) (to 4½% [0.045]) for each month in which both the late filing and late payment penalties are imposed.