K-220S: Underpayment of Estimated Tax—Partnership or S Corporation SALT Parity Tax (Revision)
Kansas · Kansas DOR · Used for tax years 2024, 2025, 2026
Kansas Schedule K-220S helps partnerships and S corporations determine whether they paid the correct amount of estimated SALT Parity Tax on time. It checks exceptions to the underpayment penalty and calculates any penalty to report on Form K-120S.
Who files this form
Schedule K-220S helps a partnership or S corporation determine whether it paid enough estimated Kansas SALT Parity Tax on time and calculate any underpayment penalty.
A partnership or S corporation must pay estimated tax if its Kansas tax liability can reasonably be expected to exceed $500 for the taxable year. The instructions state that a corporation is not required to file a declaration in its first year of existence in Kansas.
The text does not state a separate requirement for who must file K-220S.
When it's due
The supplied schedule is labeled 2025. Its instructions give these timing rules:
- 2025 tax year estimated payments: Installments are due on the 15th day of the 4th, 6th, 9th and 12th months of the taxable year.
- If a due date falls on a Saturday, Sunday or legal holiday, use the next regular workday.
- For a short taxable year, any installment-based estimated tax not paid before the 15th day of the last month must be paid on that day.
- 2025 calendar-year penalty calculation: Count days on line 10 only through December 31, 2025. The calculation beginning January 1, 2026 runs through the payment date or April 15, 2026, whichever is earlier.
The supplied text does not provide separate schedules for tax years 2024 or 2026.
What you'll need
Have these returns and records available to complete the schedule:
- Your current-year Form K-120S, including the name shown on the return and the amount on line 32.
- Your prior-year Form K-120S, including line 32.
- Your Employer Identification Number (EIN).
- Records of timely estimated tax payments and any credit carried forward, through each installment due date.
- The date tax was paid, for the penalty calculation.
- Income information for the applicable periods if you use the annualized-income exception on line 7.
Common mistakes
- Using the wrong number of days. The instructions specifically warn that lines 10 and 11 need the correct day counts to calculate the penalty on lines 12 and 13.
- Counting days after December 31, 2025 on line 10. Those days belong on line 11.
- Missing a due-date adjustment. If a due date falls on a Saturday, Sunday or legal holiday, use the next regular workday.
- Forgetting to transfer the penalty total. Enter the line 15 total on the Estimated Tax Penalty line of Form K-120S.
- Leaving the annualizing box unchecked. If you annualize income to meet the line 7 exception, check the box within the Estimated Tax Penalty line of Form K-120S.
Questions people ask
When can I avoid an underpayment penalty?
For 2025, no penalty applies for a payment period if your payments on line 5 equal or exceed the amount under an applicable exception on line 6 or line 7 for that same period.
How does Exception 1 work?
Use the smaller of 90% of the current-year tax liability or the prior-year tax liability. Line 6 uses cumulative percentages of that amount: 25%, 50%, 75% and 100% for the four installments.
Can I use annualized income?
The instructions allow a partnership or S corporation to annualize income if its estimated payment was at least 90% of the tax computed on annualized taxable income for the specified months preceding an installment date. This is Exception 2 on line 7.
What penalty rates does this schedule use?
The supplied 2025 schedule uses 9% through December 31, 2025 and 8% beginning January 1, 2026. For fiscal-year filers, the instructions state that the 8% rate remains effective through December 31, 2026.