2025 Oklahoma State Tax Deadlines
Oklahoma Individual income tax filing deadlines and extensions for 2025
If you are a resident or have been involved in business operations within Oklahoma, you might be required to file Oklahoma State taxes. Oklahoma closely follows the federal tax structure, making it relatively straightforward for taxpayers familiar with federal requirements. This comprehensive guide outlines the key tax deadlines and considerations applicable to Oklahoma in 2025.
Oklahoma business tax deadlines for 2025
C Corporations' deadlines and requirements
Oklahoma C Corporations must file and pay Corporate Income Taxes by May 15, 2026.
Filing requirements include the following:
- Complete Form OK 512 – Oklahoma Corporation Income Tax Return
- File online with the Oklahoma Tax Commission
- File by mail must be postmarked by the due date
- Payment must be made by May 15, 2026
Extension to file taxes in Oklahoma for 2025
The Extension Deadline for Oklahoma Corporate income tax returns is December 15, 2026. Oklahoma automatically grants a seven-month extension on filing Corporate income tax returns if a federal extension is filed. This is an extension to FILE, not an extension to PAY—payment is still due May 15, 2026.
Pass-through entities
Oklahoma S Corporations and Partnerships tax deadlines for 2025
S Corporations and Partnerships must file in Oklahoma by April 15, 2026.
Required forms include Form 512-S, the Oklahoma Small Business Corporation Income and Franchise Tax Return, and Form 514, the Oklahoma Partnership Income Tax Return.
Extension to file S Corporations and Partnerships taxes in Oklahoma for 2025
The Extension Deadline for Oklahoma S Corporations and Partnerships returns is October 15, 2026. Oklahoma automatically grants a six-month extension on filing pass-through entity tax returns if the federal extension is filed. This is an extension to FILE, not an extension to PAY—payment is still due April 15, 2026.
Oklahoma Individual tax considerations for 2025
Filing requirements and income thresholds
Oklahoma Individuals must file a State income tax return if their gross income exceeds the standard deduction for their filing status.
Oklahoma employs a graduated tax rate system, with rates ranging from 0.25% to 5%, depending on income level and filing status.
Estimated tax deadline for Oklahoma 2025
Estimated tax payments are due on these dates:
- April 15, 2025
- June 15, 2025
- September 15, 2025
- January 15, 2026
Use Form OW-8-ES to calculate and submit quarterly estimated payments.
Who must make estimated payments
You must make Oklahoma estimated income tax payments during 2025 if you expect to owe more than $1,000 in tax after withholding and credits. This applies to both residents and nonresidents with Oklahoma-source income.
Individual tax deadline for Oklahoma 2025
You must file and pay Individual Income Taxes in Oklahoma by April 15, 2026. Oklahoma accepts electronic filing through the Oklahoma Taxpayer Access Point (OkTAP).
Available forms include Form 511 for Residents, Form 511NR for Nonresidents, and Form 511X for amended returns.
Extension to file taxes in Oklahoma for 2025
The Extension Deadline is October 15, 2026, to file your Oklahoma Individual Income tax return. Oklahoma automatically grants a six-month extension if a federal extension is filed. This is an extension to FILE, not an extension to PAY—payment is still due April 15, 2026.
What Oklahoma tax professionals need to know
Several considerations make Oklahoma's tax landscape noteworthy for 2025. Oklahoma has reciprocity agreements with Arkansas and Kansas, which means residents of these states working in Oklahoma may not need to file Oklahoma returns. The State also offers various tax planning opportunities through credits and deductions.
Disaster relief extensions
Due to severe weather events, including wildfires that occurred in March 2025, some Oklahoma taxpayers may qualify for extended deadlines through November 3, 2025. Individuals affected should consult with the Oklahoma Tax Commission for specific eligibility requirements.
Oklahoma's unique tax features
Oklahoma offers a standard deduction that mirrors federal amounts, making tax preparation more straightforward. The State also provides favorable treatment for certain retirement income and military pay. Business income deductions are available for qualifying small business owners.
Oklahoma tax compliance best practices
Oklahoma encourages electronic filing through its OkTAP system, which provides faster processing and refund delivery. The State offers comprehensive tax-saving strategies for both Individuals and businesses.
Farmer-specific provisions
Oklahoma provides special provisions for farmers whose agricultural income represents at least two-thirds of their total gross income. These taxpayers may pay estimated tax at any time on or before January 15, 2026, or file their return by March 1, 2026, and pay the total tax at that time without making estimated payments.
Military benefits
Oklahoma does not tax military retirement pay and provides favorable treatment for active-duty military personnel. This makes it an attractive State for military families planning their retirement income strategies.
Oklahoma local tax considerations
Many Oklahoma municipalities impose local income taxes that vary by jurisdiction. Taxpayers should verify their specific regional requirements, as these taxes are separate from State obligations. Using automated tracking systems can help ensure compliance with multiple tax jurisdictions.
Sources
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The material discussed on this page is meant for general illustration and/or informational purposes only and is not to be construed as investment, tax, or legal advice. You must exercise your own independent professional judgment, recognizing that advice should not be based on unreasonable factual or legal assumptions or unreasonably rely upon representations of the client or others. Further, any advice you provide in connection with tax return preparation must comply in full with the requirements of IRS Circular 230.
Please note that if any due date falls on a federal or state holiday or weekend, it may be adjusted to the next business day. Always verify current deadlines with the appropriate tax professional and authorities.
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