Our tax software makes it easy for you to efile your state tax return and use the correct state tax forms. Prepare and efile your Oklahoma state tax return (resident, nonresident, or part-year resident) and Federal tax return together or separately. View the federal tax return filing requirements.
The regular deadline to file an Oklahoma state income tax return is April 15. However, if you efile your return through a tax preparer or an online tax vendor, your due date will be extended to April 20. Any payment of taxes due on April 20 must be remitted electronically in order to be considered timely paid. If the balance due on an electronically filed return is not remitted electronically, penalty and interest will accrue from the original due date.
|Tax Deadline Date||Type of Income Tax Return||Filing Deadline / Due Date Description|
|April 18, 2019||2018 Oklahoma State Tax Return||Due date for Oklahoma State Income Tax Returns – income tax filing deadline|
|April 18, 2019||2018 Oklahoma State Tax Extension||Due date for Oklahoma extensions|
|October 15, 2019||2018 Oklahoma State Tax Return||Last day to efile a 2018 Oklahoma State Income Tax Return for tax extension filers and late efilers|
View all state tax return filing deadlines.
Find federal income tax return filing deadlines.
We supports all of the forms that Oklahoma allows to be efiled. You can efile any of the following Oklahoma state tax forms:
|Form/Schedule||Description||Can I efile this form?|
|Form 511/511NR||Individual Income Tax Return-Resident, Nonresident/Part-Year|
|Form 511-B/511NR (Schedule A)||Individual Income Tax Return-Resident, Nonresident/Part-Year-Additions|
|Form 511-A/511NR (Schedule B)||Individual Income Tax Return-Resident, Nonresident/Part-Year-Subtractions|
|Form 511/511NR (Schedule C)||Adjustments|
|Form 511/ 511NR (Schedules G and F)||Donations from Refund|
|Form 511CR||Other Credits (Pages 1-3)|
|Form 511TX||Credit to Tax Paid to Another State|
|Form 538H||Property Tax Credit|
|Form 538S||Sales Tax Relief Credit|
|Form OK||Use Tax|
|Form OK – 2210-OW-8-P||Underpayment of Estimated Taxes|
The amended tax return should be filed within 3 years of the filing deadline for the original tax return, or 2 years from the time when tax was paid, whichever is later.
According to Oklahoma tax law, if you or the IRS made changes to your federal income tax return, then you must file a tax amendment form. Before filing the form, if you wish to avoid delays with your Oklahoma tax amendment, you must make sure to have confirmation from the IRS that the changes to your federal income tax return have been processed.
You have two options to file your amended Oklahoma tax return: