Kansas Sole Proprietorship Tax Deadlines 2026

Complete guide to Sole Proprietorship filing dates, extensions, estimated payment schedules, and required forms in Kansas for the 2026 tax year. Kansas imposes a state income tax, so Sole Proprietorship entities must file both federal and state returns.

Kansas Sole Proprietorship filing deadline

Conforms to the federal calendar-year due date unless the state announces relief.

Soon

Due: Apr 15, 2026

Extension: Oct 15, 2026

Form: State income tax return

Estimated payments

Quarterly estimated payment dates: Apr 15, 2026, Jun 15, 2026, Sep 15, 2026, Jan 15, 2027.

Soon

Due: Apr 15, 2026

Kansas Sole Proprietorship Tax Calendar at a Glance

EventDate
Filing deadlineApr 15, 2026
Extension deadlineOct 15, 2026
Q1 estimated paymentApr 15, 2026
Q2 estimated paymentJun 15, 2026
Q3 estimated paymentSep 15, 2026
Q4 estimated paymentJan 15, 2027

FAQ

When is the Sole Proprietorship tax filing deadline in Kansas for 2026?

The Kansas Sole Proprietorship tax return is due Apr 15, 2026 for the 2026 tax year. An extension is available until Oct 15, 2026.

Does Kansas require Sole Proprietorship estimated tax payments?

Yes, Kansas requires estimated tax payments for Sole Proprietorship entities. The quarterly due dates are: Apr 15, 2026, Jun 15, 2026, Sep 15, 2026, Jan 15, 2027. Penalties may apply if you underpay or miss a deadline.

What form do I file for a Sole Proprietorship in Kansas?

Sole Proprietorship entities in Kansas file using Form State income tax return. You can download the form from Kansas Department of Revenue at https://www.ksrevenue.gov.

Can I get an extension for my Kansas Sole Proprietorship tax return?

Yes. Kansas allows an extension for Sole Proprietorship returns until Oct 15, 2026. Note that an extension gives you more time to file, not more time to pay — any tax owed is still due by the original deadline of Apr 15, 2026.

What are the penalties for filing late in Kansas?

Kansas typically charges a failure-to-file penalty (usually 5% of unpaid tax per month, up to 25%) and a failure-to-pay penalty (usually 0.5-1% per month). Interest also accrues on unpaid balances. Filing for an extension by the original deadline avoids the failure-to-file penalty but not the failure-to-pay penalty.

Where can I file Kansas Sole Proprietorship taxes?

File through Kansas Department of Revenue. Visit https://www.ksrevenue.gov for e-filing options, downloadable forms, and payment portals.

Kansas Estimated Tax Payments

View the full quarterly estimated payment schedule for Kansas, including all entity types and payment methods.

View Kansas estimated payments →

Other Entity Types in Kansas

Sole Proprietorship Deadlines in Neighboring States