The Oregon Medical Marijuana Act (OMMA) was passed by Oregon voters on November 3, 1998, and took effect on December 3, 1998. The law allows a patient with a valid ID card to use, possess, and cultivate cannabis for medicinal purposes. OMMA also allows a patient to designate a primary caregiver to help the patient with his or her medicine.

The Oregon Health Authority (OHA) regulates OMMA through the Oregon Medical Marijuana Program (OMMP). A patient must enroll in the OMMP patient registry and possess a valid identification card in order to be protected from arrest. A patient who is not registered with the OMMP has an affirmative defense if the patient has a valid recommendation for a qualifying condition and is within the possession or cultivation limits set by the OMMA . 

On August 14, 2013, Governor John Kitzhaber signed House Bill 3460 (HB 3460) into law, establishing regulations for the creation of state-licensed medical cannabis facilities. The OHA developed rules and regulations and has oversight of the new statewide distribution system. The rules have been in place since January 31, 2014, allowing time for OHA to establish a process for the submission of applications for dispensaries by March 1, 2014, as required by the provisions of HB 3460. However, in early 2014, the Oregon Legislature passed SB 1531, which grants cities and counties the right to pass moratoriums on opening medical marijuana facilities in their jurisdictions until May 1, 2015.

The 2015 legislative session brought three more bills that make changes to the medical cannabis program. HB 3400 primarily changes residency requirements for growers; SB 460 allows dispensaries to temporarily serve the new legal adult-use cannabis market before the official opening of adult-use retail distribution; SB 844 develops a task for to evaluate medical and public health effects of cannabis.

In 2015, the legislature renumbered the rulemaking authority of OHA under Oregon Revised Statute § 475B.525. Moreover, the legislature relaxed limitations on marijuana possession and cultivation, effective March 1, 2016.

In 2016, the legislative session added three bills that changed the medical cannabis program. HB 4014 allows out-of-state ownership/investment in medical cannabis businesses, SB 1524 reduces annual medical marijuana card registration fees for veterans from $200 to $20 and relaxes pretrial release conditions for medical marijuana; and SB 1598 adds medical and research marijuana as recognized farm crops.

It is important to note that, since July 1, 2015 the possession of marijuana in 1 ounce or less in quantity is legal anywhere in Oregon except prohibited public places. Adults at their home can possess:

  • 8 ounces of dried flowers;
  • 72 ounces of infused liquids;
  • 16 ounces of infused solids; and
  • 1 ounce of extracted oil.

Adults, at their home may also lawfully cultivate 4 plants per household. These changes are contained within Ballot Measure 91 (2014) as amended by HB 3400 (2015).

The 2017 Legislative Session brought several changes to Oregon's medical cannabis program. Oversight of producers was shifted to  the Oregon Liquor Control Commission, requiring seed to sale tracking to prevent diversion SB 1057. 1057 also limited the number of immature plants a cardholder could have reducing it to 12 from 18, unless the address is a registered grow site. HB 2198 Established the Oregon Cannabis Commission  to review the OMMP.  This bill allowed a medical grow site to transport up to 20 pounds of cannabis a year to a recreational wholesaler. 



The Oregon Medical Marijuana Act (Oregon Revised Statutes 475.300 to 475.346)

  • Senate Bill 1511
    2016 session, effective March 29, 2016
    Makes several changes to the laws governing medical marijuana.
  • House Bill 4014
    2016 session, effective March 3, 2016
    Makes several changes to the laws governing medical marijuana.
  • Senate Bill 1598
    2016 session, effective March 3, 2016
    Makes several changes to the laws governing medical marijuana.
  • Senate Bill 844​
    2015 session, effective August 12, 2015
    Establishes task force on researching the medical and public health properties of cannabis.
  • Senate Bill 460​ 
    2015 session, effective July 27, 2015
    Allows medical marijuana​ dispensaries, beginning October 1, 2015, to sell limited marijuana retail product to adults 21 and older in accordance with certain conditions.
  • House Bill 3400
    2015 session, effective June 30, 2015
    Makes several changes to the laws governing medical marijuana.
  • Senate Bill 1531​
    2014 session, effective March 19, 2014
    Specifies that governing bodies of a city or county may adopt ordinances that impose reasonable regulations on operation of medical marijuana facilities.
  • House Bill 3460
    2013 session, effective August 14, 2013
    Directs OHA to establish a registration system for medical marijuana facilities


Permanent rules effective June 28, 2016


Oregon Medical Marijuana Program

Landmark Legal Rulings

State v. Luster (2015)

The Oregon Court of Appeals affirmed the conviction of an illegal possession of marijuana against a defendant. The court held that the affirmative defense available to a registered medical marijuana patient was invalid because the defendant had been diagnosed with a condition over 12 months prior to the arrest (interpreting Or. Rev. Stat. Ann. § 475.319, which is currently renumbered as 475B.480 in 2015 by the Legislative Counsel).

State v. Ellis (2013)

The Oregon Court of Appeals held that defendant’s hashish constituted as “usable marijuana” under OMMA. Therefore, usable marijuana under Oregon law includes dry leaves, flowers and hashish of marijuana.

State v. Berringer (2010)

The Oregon Court of Appeals affirmed a conviction of an illegal possession of marijuana against a nonresident defendant. The court held that enforcing Oregon’s law against possession of marijuana does not violate a nonresident defendant’s right to travel from state to state.

Emerald Steel Fabricators, Inc. v. Bureau of Labor and Industries (2010)

The Supreme Court of Oregon found that the Oregon Revised Statute § 475.306(1), which authorizes the use of medical marijuana, is preempted by the federal Controlled Substances Act. This Court’s decision is limited to § 475.306(1) (currently renumbered as § 475B.433); the Court also refused to rule whether the Controlled Substances Act preempt other provisions of the OMMA that exempt the possession, manufacture, or distribution of medical marijuana from state criminal liability.