Filing requirements and guidance
Corporations that are doing business in Oregon, or with income from an Oregon source, must file an Oregon corporation tax return. Public Law 86-272 provides filing exceptions for foreign corporations doing business in Oregon.
If a corporation is doing business in Oregon, they generally must file an excise tax return for the privilege of doing business in Oregon. Excise tax is measured by net income. Excise tax filers are subject to corporation minimum tax.
If a corporation is not doing business in Oregon, but has income from an Oregon source, they generally must file an income tax return. Income tax filers are not subject to corporation minimum excise tax.
Registering your corporation with the Secretary of State office or with the Department of Consumer and Business Services Insurance Division doesn't create a tax filing requirement. If you are not doing business in Oregon and don't have income from an Oregon source, you don't need to file a tax return in Oregon. Filing a return may result in minimum tax due.
Insurance excise tax
Insurance companies must file an Oregon excise tax return if they're doing business in Oregon. This includes companies with agents in Oregon whose only activity is solicitation, and those with income from an Oregon source, such as premiums from existing policyholders.
Foreign and domestic insurance companies, including home warranty companies, must file an insurance excise tax return, Form OR-20-INS. Title insurers must file a Form OR-20. See form instructions for details.
All insurance companies required to file must do so on a calendar year basis and are subject to the minimum tax. Estimated tax payments may be required.
Foreign insurers and domestic insurers controlled by foreign insurers are required to file insurance excise tax returns separately. Domestic insurance companies that are incorporated in Oregon, and not controlled by foreign insurers incorporated outside of Oregon, must file consolidated returns if they were included in consolidated federal returns.
C corporation minimum tax and tax rates
C corporation excise tax filers, including insurance companies, pay the minimum tax or calculated tax, whichever is greater. C corporation income tax filers pay calculated tax (if any), but not minimum tax.
Calculated tax for tax years beginning January 1, 2013 and later:
- If Oregon taxable income is $1 million or less, multiply Oregon taxable income by 6.6 percent (not below zero).
- If Oregon taxable income is more than $1 million, multiply the amount that is more than $1 million by 7.6 percent, and add $66,000.
- For tax years beginning before January 1, 2013 see the specific year's form instructions.
S corporations
For Oregon, S corporation income is generally taxable to the shareholders rather than the corporation. However, the entity is subject to Oregon tax on income from built-in gains and excess net passive income, if such income is taxed on the federal S corporation return.
An S corporation carrying on or doing business in Oregon must also pay $150 minimum excise tax. The minimum tax does not flow through to the shareholders.
The income or loss of an S corporation is reported to each shareholder on federal form Schedule K-1. See shareholder filing requirements for more information.
S corporation minimum tax and tax rates
S corporation excise tax filers pay the minimum tax or calculated tax, whichever is greater. S corporation income tax filers pay calculated tax (if any), but not minimum tax.
Calculated tax for tax years beginning January 1, 2013 and later:
- If Oregon taxable income is $1 million or less, multiply Oregon taxable income by 6.6 percent (not below zero).
- If Oregon taxable income is more than $1 million, multiply the amount that is more than $1 million by 7.6 percent, and add $66,000.
- For tax years beginning before January 1, 2013 see the specific year's form instructions.
Minimum tax, only for excise tax filers: $150.
Shareholder filing requirements
Shareholders who meet Oregon filing requirements must file an Oregon tax return. Refer to the appropriate tax forms and instructions, based on what type of taxpayer the shareholder is (individual, corporation, trust, other), for more information.
Resident shareholders are taxed on their pro rata share of S corporation income, losses, and deductions from the federal K-1s. Those amounts are modified by Oregon additions and subtractions.
Nonresident shareholders are taxed on their share of modified income from the federal K-1s, multiplied by the S corporation's apportionment percentage from Schedule OR-AP.
Each shareholder may claim their pro rata share of the S corporation's business tax credits (ORS 314.772 and OAR 150-314-0505). The credits are claimed for the tax year in which the S corporation's tax year ends.
S corporations and other pass-through entities with nonresident shareholders or owners may have more filing and payment requirements. See Publication OR-OC and Form OR-19 for more information.
Tie to federal tax law
In general, Oregon is tied to the federal definition of taxable income as of December 31, 2022. However, Oregon is still disconnected from:
- Federal subsidies for prescription drug plans (IRC §139A; ORS 317.401).
- Deferral of certain deductions for tax years beginning on or after January 1, 2009 and before January 1, 2011 may require subsequent Oregon modifications (IRC §168(k) and §179; ORS 317.301).
Due dates
Oregon corporation returns are due the 15th day of the month following the due date of your federal corporation return. For example, if a calendar year federal C corporation return is due April 15, the Oregon calendar year return is due May 15. If a calendar year federal S corporation return is due March 15, the Oregon calendar year return is due April 15. If a due date falls on a weekend or state holiday, the return is due the next business day. Corporation due dates aren't affected by Emancipation Day.
Extensions
We don't have an extension form for Oregon; use federal extension Form 7004. Include the extension when you file your Oregon return, don't send it separately. Mark the "Extension" box on the first page of your Oregon return. If you need an extension to file for Oregon only, write “for Oregon only" across the top of the form before filing.
The Oregon corporation extended due date is the 15th day of the month following the federal extended due date. See the corporation
form instructions for more details.
Corporation estimated tax
You must make quarterly estimated tax payments if you expect to owe $500 or more in tax for the year. If you don't make estimated tax payments as required, you may be subject to interest on underpayment of estimated tax (UND).
For more information, including how to calculate your next year's estimated tax, see instructions for the Oregon corporation form you will file (Form OR-20, OR-20-INC, OR-20-INS, or OR-20-S) and ORS 314.505 – 314.525 and supporting administrative rules.
Payment options
Estimated payments can be made using one of these options:
You must make your Oregon estimated payments by EFT if you're required to make your federal estimated payments by EFT. If this requirement creates a disadvantage for you, you may be eligible for a waiver. See ORS 314.518 and OAR 150-314-0310 or email us for more information.
If you don't meet the federal requirements for mandatory EFT payments, you can participate on a voluntary basis.
Payment due dates
Estimated tax payments are due quarterly, as follows:
- Calendar year filers: April 15, June 15, September 15, and December 15.
- Fiscal year filers: The 15th day of the 4th, 6th, 9th, and 12th months of your fiscal year.
If the due date falls on a Saturday, Sunday, or legal holiday, use the next regular business day.
Market-based sourcing
Starting with the 2018 tax year, taxpayers must use
market-based sourcing principles for certain receipts, excluding those from the
sale of tangible personal property. See OAR 150-314-0435 for more information.
Amended returns
Oregon doesn't have a specific amended return form for corporations. Use the same form type originally filed for the tax year you're amending and check the "amended" box. See the form instructions for more information and requirements. File your amended return separately from your current year's return.
Important: Generally, don't amend your return to carry back a corporation net operating loss. Oregon only allows corporations to carry back net operating losses if the corporation is engaged in crop production, animal production, or aquaculture. See ORS 317.346 for more information.
Federal audit changes
If the IRS changes your federal return for any tax year, you must notify us. File an amended Oregon return and include a copy of the federal audit report. Mail this separately from your current year's return.
If you don't amend or send a copy of the federal report, we have two years from the date the IRS notifies us of the change to issue a deficiency notice. You must file an amended return within two years of the date of the federal report to receive a refund.
Protective claims
Don't file an amended return as a protective claim. Use Oregon Form OR-PCR, Protective Claim for Refund, when your claim to a refund is contingent on a pending court decision or legislative action. Notify us within 90 days of the final determination by filing an amended return. Don't file an amended return before the pending action is final.
Frequently asked questions