File Your OK Taxes Faster

Oklahoma State Sign

All residents, partial-year residents and nonresidents of Oklahoma must file an annual income tax return if they earn money in the state during the applicable tax year. This also applies to students and dependents who earn money. Nonresidents and partial-year residents must use Form 511NR. Residents must use form 511. Taxpayers who file online with us and owe money that want to mail their payment, can complete the Form 511V and send it to the Tax Commission at:

PO Box 26890
Oklahoma City, OK 73126-0890

With annual tax revenue of more than $8 billion, Oklahoma falls in the nation's median tax revenue range. The state income tax rate varies between 0.5% and 5%, which is lower than the national average. Oklahoma state income tax returns must be e-filed or mailed by April 15. All extension requests must be mailed by this date as well. Extended returns are due by October 15.

Tax extension requests grant taxpayers extra time to file their returns. However, this does not allow extra time to pay tax due. Extension requests are not granted unless taxpayers pay at least 90% of the OK taxes they owe on or before April 15. To contact the Tax Commission with an extension request, use Form 504 and mail to:


Income Tax


PO Box 26890

Oklahoma City, OK 73126-0890

If errors are discovered on prior returns and an amendment is needed, use Form 511 for residents or Form 511NR for partial-year residents and nonresidents. Mail the forms to the Tax Commission and any required payment to the address:


PO Box 26800

Oklahoma City, OK 73126-0800

OK Taxpayer Access Point


To check the status of a state tax refund online, use the Taxpayer Access Point page at https://oktap.tax.ok.gov/oktap/web/.

Taxpayers can also check refund status over the phone by calling 405-521-3160. For questions about prior returns, amendments and other return topics, call 405-521-3160.

If Oklahoma taxpayers are self-employed or have inadequate amounts of tax withheld from their paychecks, they may be required to make quarterly estimated tax payments. Use Form OW-8-ES to determine this. If payments must be made, mail them with their vouchers by the due dates indicated on the worksheets to the Oklahoma Tax Commission, at the address on the form.

If State Taxes Due are Delinquent


If OK taxes due are not paid by April 15, the Tax Commission may charge a late payment fee of 5% of the tax owed. In addition to this, an interest charge of 1.25% of the amount due accrues monthly until the balance is paid.

Note: States & U.S. territories may make changes to their tax laws with little notice. We do our best to keep this information up-to-date, but it is provided on an "AS IS" basis. For more see our terms.

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