Where is My Refund?   |   October 15 Deadline   |   Why eFile?

Oklahoma Income Taxes and OK State Tax Forms

OK tax return filing and payment due date for Tax Year 2020 is April 15, 2021 May 17, 2021. Oklahoma State Individual Taxes for Tax Year 2020  (January 1 - Dec. 31, 2020) can be prepared and e-Filed now with an IRS or Federal Individual Tax Return (or you can learn how to complete and file only an OK state return).  Find IRS or Federal Tax Return deadline details.

efile Oklahoma tax return
"The Sooner State"

The 2020 Oklahoma State Income Tax Return forms for Tax Year 2020 (Jan. 1 - Dec. 31, 2020) can be e-Filed together with the IRS Income Tax Return by the April 15, 2021 May 17, 2021 deadline. If you file a tax extension you can e-File your Taxes until October 15, 2021 without a late filing penalty. However, if you owe Taxes and don't pay on time, you might face late tax payment penalties. Tip: File on time, even if you can't pay on time, as the late filing penalties are higher than the late payment penalties.

eFile.com makes it easy for you to e-file your IRS an Oklahoma State Tax Return (e.g resident, nonresident, or part-year resident returns). However, the IRS and the respective State Tax Agencies require you to e-file a Federal Income Tax Return at the same time you e-file a State Tax Return. This is not an eFile.com policy but an IRS and State Agency policy. Therefore, you cannot e-File an Oklahoma Tax Return anywhere - not just eFile.com - without also e-filing the associated IRS Tax Return. However, please read on for good news. 

Find detailed instructions on how you can only prepare and mail in - not eFile - an Oklahoma 2020 Tax Return - here via eFile.com. However, you must download/print and sign the forms and mail them to the Tax Agency.

Where Is Your Oklahoma Tax Refund Money?
Step 1: Sign into your eFile.com account and check acceptance by the Tax Agency.
Step 2: Check your Oklahoma Tax Refund Status.
Where is Your IRS Refund?
Step 1: Sign into your eFile.com account and check acceptance by the IRS.
Step 2: Check your IRS Tax Refund Status.
Automatic Oklahoma Income Tax Extension
Oklahoma Income Tax Amendment
How to correct a rejected Tax Return
If your OK Tax Return was rejected by the OK Tax Agency - not eFile.com - instructions on how to correct a rejected Oklahoma Tax Return.
Oklahoma IRS Late Filing, Tax Payment Penalties

1. Late Filing Penalty: There is only a late payment penalty as detailed below.

2. Late Payment Penalty: A delinquent penalty is charged when at least 90% of the tax is not paid by the deadline. The penalty amounts to 5%. A one-time 5% delinquent penalty and interest accruing at 1.25% per month will be charged on any taxes owed not paid by the original tax return due date.

3. IRS Penalties: Calculate and Estimate your potential IRS Income Tax Return Penalties.
OK Tax Return Mailing Addresses
Find various Oklahoma Mailing Addresses for tax returns, tax amendments, and tax payments. 
Oklahoma Income Tax Brackets
Oklahoma Income Tax Forms
Oklahoma Unemployment Benefits
Oklahoma applies state taxes to unemployment income at the federal level.


Start Federal and Oklahoma Tax Returns

2021 Oklahoma Income Tax Filing Deadlines by Tax Year

The majority of deadlines listed here are for Tax Year 2020. Some apply to upcoming Tax Years and some are IRS or Federal deadlines.

April 15, 2021
Tax Year 2020
Income Tax Return
Prepare and e-File an IRS (Due Date April 15, 2021) and Oklahoma State Income Tax Return (Due Date April 15, 2021) until October 15, 2021. - eFileIT*
April 15, 2021
2020 Income Tax Extension
October 15, 2021
Tax Year 2020
Income Tax Return after the April 15, 2021 Oklahoma Tax Extension
Last day to e-File a 2020 Oklahoma State Income Tax Return for Tax Extension Filers and late eFilers. You can only e-File (to file by paper see below) Oklahoma Income Tax Return together with an IRS Tax Return. eFileIT*
October 15, 2021 via mail-in Forms.
Forms incl. Mailing Address are listed below.
Tax Year 2020
Income Tax Return after the April 15, 2021 Oklahoma Tax Extension
Deadline for taxpayers who got an OK Tax Extension to file their OK Income Tax Return by mail-in Forms - the Forms incl. mailing addresses are listed below - is October 15, 2021. (Optionally, the eFileIT* deadline is Oct. 15, 2021). Instructions on how to only - without the IRS return - prepare and file an Oklahoma State Income Tax Return on eFile.com.
Tax Amendment for all Tax Years
IRS Due Dates
IRS Tax Return, Extension, Amendment Deadlines
2021, 2022, etc.
Other State Tax Return, Extension, Amendment Deadlines
Select respective State Tax Return Deadlines.
2021, 2022, etc.
IRS Federal Income Tax Return, Amendment, Extension Deadlines
April 15, 2024
2020 Oklahoma Income Tax Return Refund.
IRS Tax Return Refund Claim Deadline
The last day to file - you will not face late filing penalties - and claim your 2020 Oklahoma Income Tax Return Refund. This deadline does not apply if you owe 2020 Income Taxes.

E-File These 2020 Oklahoma State Tax Forms

Prepare and e-file these state forms for 2020 in conjunction with your federal and state income tax return. As you proceed through the tax interview on eFile.com, the application will select the correct state forms for you. You can also select tax forms individually. All these forms will then be e-filed by you to the state tax agency. Instructions on how to only prepare a state income tax return.

eFileIT Now*
Form 511
Individual Resident Income Tax Return
Form 511NR
Individual Nonresident/Part-Year Income Tax Return
Form 511CR
Other Credits
Form 538H
Property Tax Credit
Form 538S
Claim for Credit/Refund of Sales Tax
Form 561
Oklahoma Capital Gain Deduction
Form 564
Credit for Employees in the Aerospace Sector
Form 577
Refundable Coal Credit
Form 578
Refundable Credit for Electricity Generated by Zero Emissions Faculties
Form OW-8-P
Underpayment of Estimated Taxes
Form 504-I
Extension Form (You can make Tax Payments online and not have to mail in Form 504-I).

* Due to IRS and State Tax Agency tax data sharing and validation requirements, you can only e-file a State Income Tax Return while also e-filing a Federal Income Tax Return. This is not an eFile.com created policy, but all online tax web sites have to adhere to this IRS/state issued tax data sharing policy. You can however prepare all 44 State Income Tax Returns on eFile.com if you have already e-Filed or filed your IRS return. Instructions on how you can ONLY prepare and file State Income Tax Return(s). Only on eFile.com can you prepare, file or e-file unlimited State Tax Returns for one low price and not pay for each State return like you would do on H&R Block® vs. TurboTax®. Dare to Compare Now.

Automatic Oklahoma Tax Extension

For Tax Year 2020 you can e-File an IRS Tax Extension by April 15, 2021 for free on eFile.com (instructions on whether you should consider a Tax Extension or not). 

If you are certain that you cannot file your Oklahoma return by the deadline, you do not need to file for an extension. You will automatically receive a 6-month extension of time to file your return (not to pay). The extended tax return due date is October 15, 2021. Please be aware that Oklahoma will not accept the federal extension form as an extension for your Oklahoma tax return. If you expect to owe income taxes, you should submit your payment online at OK TAP.  If you are making a payment electronically, Form 504-I is not needed. However, if you e-filed your return and are making a payment by check or money order, you must complete a Form 504-I on eFile.com. Use eFile.com and prepare an Oklahoma tax return to find out what your Oklahoma state income tax payment will be.

The extended IRS/Oklahoma eFile deadline is Oct. 15, 2021 - eFileIT*. If you plan to file or mail-in a Oklahoma tax return on paper - the Forms and Mailing Address are below - your due date is Oct. 15, 2021. After Oct. 15, 2021, you can complete and sign 2020 Oklahoma Tax Forms online here on eFile, before you download, print and mail them to the state tax agency. The address is on the form.

Oklahoma State Tax Payment Options
You can select one of these payment options either after you have e-filed or filed your 2020 Oklahoma Tax Return. Alternatively, you can pay Oklahoma income taxes here prior to filing (e.g in the case of an extension). Plus, you can make online Oklahoma tax estimate payments for next tax year. If you eFiled your taxes and pay online, you do not have to send in Oklahoma paper forms (e.g. payer tax return, extension form, or tax estimate form). 
Go to the Oklahoma TAP site to submit your payment. Make sure you select "Individual Income Tax" as the account type, and "Return Payment" as your payment type.
This is a free option if you want to pay your taxes owed via your bank account.
Submit a tax payment through OK TAP site. When you're on the site, select the "Individual Income Tax" option, then follow the on-screen prompts to enter and submit your information (e.g. SSN, Tax Year, Form Type, Coupon).
Use this payment option if you want to pay your tax payment via your credit or debit card. There is an additional fee of 2.25% of the total payment amount plus $2.00 convenience fee added to each payment you submit with your card.
Check or Money Order with Form 511-V
Complete voucher Form 511-V and attach it to your check or money order payable to "Oklahoma Tax Commission".  Mail them to the Form 511-V address below.
Use this payment option if you wish to submit your payment via check or money order in the mail. 
Estimated Tax Payment Options
Choose one of these options: 1) Go to Oklahoma TAP site to submit your estimated payment and choose "Individual Income Tax" as Account Type and "Quarterly Estimated Payment" as Payment Type.  2) Pay via ACH credit by sending tax payments from your bank account to Oklahoma Tax Commission bank account.  On the payment screen, you can choose between checking or savings account.  After submitting your information, print or save your payment confirmation for record keeping.  3) Pay via credit or debit card through OK TAP (and follow the directions above and choose your credit card as your Payment Type). Be aware that a service fee is added to each payment you submit with your card. 4) Complete Form OW-8-ES. Attach a check or money order for the tax period payable to " Oklahoma Tax Commission".  Mail the coupon and check/money order to the Form OW-8-ES address here.
Use one of these payment options if you want to submit estimated taxes rather than submit all your taxes owed at once. 
Many of these online IRS tax payment options can be used before or after you e-Filed your Income Taxes. You can pay tax extension and tax estimate payments. For estimate payments, you do not have to submit a form. Extension you can eFile on eFile.com for free.
These payment options are independent from you preparing and eFiling your tax returns on eFile.com. eFile.com offers these payment options for the convenience of all tax payers.


Oklahoma Tax Return, Amendment, etc. Mailing Addresses
Addresses to mail Oklahoma Tax Returns, Amendments, Extensions, or Tax Payments.
OK Tax Return or Amended Tax Return
Oklahoma Tax Commission
Post Office Box 26800
Oklahoma City, OK 73126-0800
OK Tax Return or Amended Return: 2-D Form
Oklahoma Tax Commission
Post Office Box 269045
Oklahoma City, OK 73126-9045
OK Tax Extension: Address if you owe Taxes and include payment. Tax Extension Payments, include Form 504-I. Tip: Make Tax Payments online and you will not have to mail in the Form 504-I.  See above.
Oklahoma Tax Commission
Income Tax
P.O. Box 26890
Oklahoma City, OK 73126-0890
OK Tax Payment: include voucher Form 511-V
Oklahoma Tax Commission
P.O. Box 26890
Oklahoma City, OK 73126-0890
OK Tax Estimate Payments: include Tax year 2021 Form OW-8-ES
Oklahoma Tax Commission
P.O. Box 269027
Oklahoma City, OK 73126-9027


Other U.S. States, Territories, and Protectorates.