You can pay Kansas state taxes online for free by using the Kansas Tax Payment Portal or KS WebFile with a bank account (ACH debit). Credit card payments go through the same portals but carry a processor convenience fee that the Department of Revenue does not set. Businesses use the Customer Service Center to file and pay in one place.
The Three Online Payment Routes
Kansas offers three separate online tools, and picking the right one depends on whether you still need to file, whether you just want to send money, and whether you’re paying as an individual or a business.
KS WebFile
KS WebFile is the option if you haven’t filed your Kansas individual income tax return yet. It lets you file the return and pay any balance due in a single session, free of charge. You can pay by electronic check or by credit card (Mastercard, Discover, or American Express), and refunds can be deposited directly into your bank account.1Kansas Department of Revenue. Electronic Filing Options for Individual Income and Business Taxes For most individual filers, this is the cleanest path.
Kansas Tax Payment Portal
The Kansas Tax Payment Portal is built for one-time payments and does not file returns. It handles any tax type, including regular balances due, extension payments, and quarterly estimated payments.2Kansas Department of Revenue. Make a Tax Payment Paying by ACH debit directly from your bank account is free. Credit card is accepted, but the card processor charges a convenience fee that is not set by the Department of Revenue.3Kansas Department of Revenue. Frequently Asked Questions About Credit Card Payments You select the tax type, enter the amount, provide your banking or card details, and receive immediate confirmation.
Customer Service Center
The Customer Service Center is the broader account portal. After you register with an email and password, you can make electronic payments, file business tax returns (sales, use, and withholding), and view account activity in one place.4Kansas Department of Revenue. Customer Service Center This is the only online route for electronically filing most Kansas business tax returns, because the Tax Payment Portal accepts payments only.2Kansas Department of Revenue. Make a Tax Payment
What It Costs to Pay Online
Bank account payments through any of the three tools are free. Credit card payments carry a convenience fee charged by the card processor, not the state, so the cost varies by processor rather than by tax type.3Kansas Department of Revenue. Frequently Asked Questions About Credit Card Payments Kansas accepts Mastercard, Discover, and American Express for individual income tax through KS WebFile.1Kansas Department of Revenue. Electronic Filing Options for Individual Income and Business Taxes If cost is the deciding factor, ACH debit from a checking or savings account is the answer.
What to Have Ready Before You Start
Before opening a payment portal, know exactly what you’re paying. For individual income tax, that means having your Form K-40 figures in hand, along with the federal return, W-2s, and any 1099s that fed into it.5Kansas Department of Revenue. Individual Income Tax Forms Kansas also requires Schedule S for adjustments to federal adjusted gross income, and Schedule A if you’re itemizing. Confirming the number before you pay prevents the awkward second payment or refund request later.
For the payment itself, you’ll need:
- Your Social Security number (or business tax account number)
- The tax type and tax year you’re paying
- The exact amount
- Bank routing and account numbers, or a valid credit card
Paying an Extension or Estimated Payment Online
The same portals handle more than just a return balance. If you filed a federal extension on IRS Form 4868, Kansas automatically extends your filing deadline to match, but the extension covers filing only, not payment. At least 90% of your total Kansas tax liability still has to be paid by April 15, 2026, to avoid a separate penalty.6Kansas Department of Revenue. Frequently Asked Questions About Individual Income – Section: How Do I File for an Extension of Time? You can submit that extension payment through the Tax Payment Portal by selecting the extension payment option.
Quarterly estimated payments also run through the Tax Payment Portal. If your expected Kansas tax after withholding and credits is $500 or more, and withholding won’t cover at least 90% of the current-year tax or 100% of the prior-year tax, you’re required to pay estimated tax. For the 2026 tax year, calendar-year estimated payments are due April 15, 2026; June 15, 2026; September 15, 2026; and January 15, 2027. Farmers and fishers follow a different schedule and may make a single payment by January 15 of the following year.7Kansas Department of Revenue. Kansas Individual Estimated Tax K-40ES
Business Payments Online
Kansas businesses handle sales tax, use tax, withholding, and other business tax types through the Customer Service Center, which supports both filing and payment. The Tax Payment Portal also takes one-time business tax payments if all you need to do is send money.2Kansas Department of Revenue. Make a Tax Payment
Some businesses are required to pay electronically. Employers with a total withholding tax liability exceeding $45,000 in any calendar year may be required to remit payments by electronic funds transfer, and all sales and use tax payments from streamlined sales tax model sellers must be submitted electronically.8Kansas State Legislature. Kansas Statutes 75-5151 – Electronic Funds Transfers; Authority of Secretary of Revenue Below those thresholds, electronic payment is optional but generally faster than mailing checks.
If You Can’t Pay the Full Amount
You can still make a partial payment online through the Tax Payment Portal to reduce the balance the penalty and interest run against. From there, individuals apply for a payment plan using Form CM-15, which is faxed to 785-291-3616 or emailed to kdor_kstaxpayplanrequest@ks.gov.9Kansas Department of Revenue. Payment Plan Request for Businesses and Individuals There is no fully online application for the plan itself.
A few conditions attach to the plan. Plans exceeding 90 days carry a $25 administration fee added to your first payment.10Kansas Department of Revenue. CM-15 Payment Plan Request for Individuals Penalty and interest keep running on the unpaid balance during the plan, future Kansas refunds will be applied to what you owe even if you’re current on installments, and plans longer than six months may prompt the department to file a tax warrant with the district court.9Kansas Department of Revenue. Payment Plan Request for Businesses and Individuals Missing a payment or falling behind on current taxes can default the agreement.
The 2026 Deadline and What Late Costs
For the 2025 tax year, the Kansas individual income tax filing and payment deadline is April 15, 2026. If that date falls on a weekend or legal holiday, the deadline shifts to the next business day.11Kansas Department of Revenue. Pub. KS-1515 Tax Calendar of Due Dates
Late payment carries a penalty of 1% per month (or any fraction of a month) on the unpaid tax, capped at 24%. Interest for the 2026 calendar year runs at 8% annually, roughly 0.67% per month, calculated on the unpaid tax itself and not on the penalty or previously accrued interest.12Kansas Department of Revenue. Penalty and Interest On a $5,000 balance, that combined charge is about $83 each month. Paying whatever you can by the deadline through one of the online portals limits how much of that clock runs against you.
If You’d Rather Pay by Mail
If online isn’t an option, Kansas still accepts a check or money order with Form K-40V, the Kansas Individual Income Tax Payment Voucher. Make it payable to “Kansas Income Tax,” write your Social Security number on it, and mail it to Kansas Department of Revenue, PO Box 750260, Topeka, KS 66699-0260.13Kansas Department of Revenue. 2025 Kansas Individual Income Tax Payment Voucher Estimated payments use a different address: PO Box 3506, Topeka, KS 66625-3506.14Kansas Department of Revenue. Individual Tax Mailing Addresses Sending a payment to the wrong box delays processing, so confirm the type of payment before you seal the envelope.