K-40ES: Individual Estimated Income Tax Vouchers and Worksheet (2025)
Kansas · Kansas DOR · Used for tax years 2025
Kansas Form K-40ES includes a worksheet and payment vouchers for 2025 individual estimated income tax. The worksheet calculates estimated tax after withholding and credits, and the vouchers identify the taxpayer and payment amount.
Who files this form
Use Kansas Form K-40ES to calculate and pay estimated income tax for tax year 2025.
You must make estimated payments if both conditions apply:
- Your estimated Kansas income tax after withholding and credits is $500 or more.
- Your withholding and credits may be less than the smaller of 90% of your 2025 tax or 100% of the tax shown on your 2024 return.
Income not subject to withholding can include self-employment earnings, unemployment, interest, dividends, and income earned in another state while living in Kansas. Nonresidents should consider only Kansas-source income when applying these conditions.
When it's due
For tax year 2025, calendar-year taxpayers other than farmers and fishers have these payment deadlines:
- First quarter: April 15, 2025.
- Second quarter: June 15, 2025.
- Third quarter: September 15, 2025.
- Fourth quarter: January 15, 2026.
The January payment is not required if you file your 2025 return and fully pay the tax by January 31, 2026.
Farmers and fishers: The payment for tax year 2025 is due January 15, 2026, unless you file your 2025 return and fully pay the tax on or before March 1, 2026.
Fiscal-year taxpayers: Payments are due on the 15th day of the fourth, sixth, and ninth months of the current fiscal year and the first month of the following fiscal year.
If a due date falls on a Saturday, Sunday, or legal holiday, use the next regular workday.
What you'll need
Have these materials and details available:
- The 2025 K-40ES worksheet and the correct quarterly voucher if paying by mail.
- Your expected adjusted gross income, deductions, exemptions, Kansas withholding, and tax credits for 2025.
- Your 2024 tax return to use the prior-year tax comparison.
- Your name, Social Security number, mailing address, and daytime phone number. For a joint return, include both spouses' names and Social Security numbers.
- A check or money order if mailing your payment.
The worksheet refers to page 6 of the K-40 instruction booklet for exemption amounts. If you or your spouse are 65 or older or blind, or someone else claims you as a dependent, use the standard deduction worksheets in the Kansas income tax booklet rather than the chart on K-40ES.
How to file
Pay electronically: Visit the Kansas Department of Revenue Payment portal at www.kansas.gov/payment-portal/, or visit ksrevenue.gov and log in to the Kansas Customer Service Center.
Pay by mail:
- Complete the worksheet to calculate your estimated tax for 2025.
- Use black ink and the correct voucher for the quarter. Enter all required information, including the payment amount. For a joint return, include both names and Social Security numbers.
- Write your Social Security number or numbers on your check or money order. Make it payable to Kansas Individual Estimated Tax.
- Mail the voucher and payment to:
Estimated Tax
Kansas Department of Revenue
PO Box 3506
Topeka, KS 66625-3506
Enter each payment in the worksheet's Estimated Payment Record.
Common mistakes
- Submitting photocopies: The vouchers say not to submit photocopies of the form.
- Using the wrong ink or voucher: Use only black ink and the voucher for the quarter you are paying.
- Leaving out joint-filer details: Include both names and Social Security numbers if you plan to file jointly.
- Omitting Social Security numbers from the payment: Write your SSN or SSNs on your check or money order.
- Using the wrong tax computation schedule: Use the schedule for your filing status.
- Not updating your estimate: You may need to recalculate if your income or deductions change substantially during the year.
- Paying too little: The form warns that a penalty may apply if you do not pay enough estimated tax.
Questions people ask
Are estimated payments required if my worksheet result is below $500?
No. If line 8, Kansas estimated income tax, is less than $500, estimated payments are not required.
How much is each quarterly payment?
The worksheet generally directs you to pay one-fourth of line 8 each quarter. It gives different fractions if you begin making payments later in the year.
How can I check whether I owe an underpayment penalty?
Use Schedule K-210 to figure any underpayment, check whether you qualify for a penalty exception, and calculate any penalty due. It is available at ksrevenue.gov.
Where can I get help completing the vouchers?
Call the Kansas Department of Revenue at 785-368-8222. The Taxation home page at ksrevenue.gov also offers a 24-hour Chat option and Live Agent chat Monday through Friday, 8:00 a.m. to 4:45 p.m.