5324: City of Detroit Corporate Income Tax Penalty and Interest Computation for Underpaid Estimated Tax (2025)
Michigan · Michigan Treasury · Used for tax years 2025
Michigan Form 5324 calculates penalty and interest on underpaid estimated City of Detroit Corporate Income Tax for 2025. It figures required estimated tax payments, underpayments, interest and penalties, with the total carried to Form 5297, line 48.
Who files this form
Form 5324 is for computing penalty and interest on underpaid estimated City of Detroit corporate income tax for tax year 2025. The form does not state a filing threshold or a separate requirement to file it.
What you'll need
Have the following information ready:
- Taxpayer name and Federal Employer Identification Number (FEIN).
- Total tax liability from Form 5297, line 39, for both 2025 and 2024.
- Prior-year overpayment and estimated payment amounts.
- Estimated payment due dates and the dates tax was paid.
- The annual return due date.
These details are used to calculate the required estimates, underpayments, interest and penalty.
Common mistakes
- Working across columns too soon: The form cautions you to complete lines 7 through 15 one column at a time.
- Overlooking the amendment reminder: Line 37 says to see the instructions if you are amending. No instructions were provided with this text.
Questions people ask
How is the required estimated tax calculated?
Compare the 2025 and 2024 total tax liabilities from Form 5297, line 39. Enter the lesser amount on line 3, then multiply it by 70% on line 4. Line 6 divides that result by four, or by the number of quarterly returns required.
How does the form calculate interest?
Part 2 calculates interest on the total underpayment from lines 13 and 14. It separates the days into the periods printed on lines 19 through 22 and applies the corresponding annual rates, dividing by 365. Add the interest for columns A through D on line 28.
How is the penalty calculated?
Part 3 uses the underpayment from line 14 and a monthly penalty rate of 1%. Count months, including fractional months, from the payment due date to the annual return due date or the date payment was made, whichever is earlier. Add the penalties for columns A through D on line 36.
Where does the final total go?
Add interest from line 28 and penalty from line 36 on line 37. Carry that total to Form 5297, line 48. If amending, the form directs you to see the instructions.