Legislation History

Initiative 692 (I-692), or the Medical Use of Marijuana Act of 1998 was passed with nearly 60 percent of the vote. The initiative permitted patients with certain debilitating conditions, terminal illnesses, or intractable pain, to use medical marijuana. I-692 also granted legal protections to qualifying patients and their caregivers for the possession and consumption of medical marijuana.


Initiative 502 (I-502), the Washington Marijuana Legalization and Regulation Initiative, was passed by voters on the statewide 2012 ballot with 55 percent of the vote. I-502 legalized recreational cannabis for adults 21 or older, and established a regulatory structure for the production and sale of adult-use marijuana. Before I-502, cannabis distribution, possession, or use for adult-use purposes was illegal in the state of Washington. The initiative went into effect Dec. 6, 2012, exactly 30 days after its passage and well in advance of the December 1, 2013 requirement.


In 2015, the Washington Legislature passed SB 5052, the Cannabis Patient Protection Act (CPPA), establishing official state regulations for the production, possession, sale and use of medical marijuana.


I-502 legalized adult-use marijuana production, distribution, possession, and consumption throughout Washington state. All licensing and regulation of marijuana falls under the jurisdiction of the Washington State Liquor and Cannabis Board (WSLCB).

Where is it Safe to Purchase?

Adult-use cannabis may be legally purchased only from a state-licensed retailer. Patients and caregivers may also purchase medical cannabis from any state-licensed retailer. Tribal ID cards are valid as identification if they meet the rules laid out in the Washington State Liquor and Cannabis Board website.


Under state law, all marijuana sales are subject to a 37 percent excise tax. Medical patients are not subject to sales tax.  

Where is it Safe to Consume?

It remains illegal to consume cannabis or marijuana-infused products “in view of the public.” Cannabis cannot be consumed wherever tobacco smoking is prohibited.


The law allows adults 21 and older to purchase in a single day: up to one ounce (1 oz.), or 28.35 grams, of usable marijuana; 16 ounces, or 453.59 grams, of cannabis-infused edibles in solid form; 72 fluid ounces, or 2.13 liters, in liquid form; and 7 grams, or a quarter-ounce (0.25 oz), of cannabis concentrates.


Medical marijuana patients may purchase and possess three ounces (3 oz.), or 85 grams, of usable marijuana; 48 ounces, or 1.36 kilograms of marijuana-infused products in solid form;1.69 gallons, or 6.4 liters of marijuana-infused products in liquid form; or 21 grams (595.34)of marijuana concentrate.


Driving under the influence of cannabis is illegal and consumption in a vehicle is neither allowed for drivers nor for passengers. Consumers can carry cannabis in their vehicles, but it must be in a sealed container or in the trunk. However, it is illegal to transport any open package or container of cannabis or marijuana-infused products. It remains illegal to transport cannabis from across state lines. Washington State stipulates that more than 5 nanograms of active THC per milliliter of blood is the limit for driving, and a blood test can be performed at a police station or a medical facility. The state advises waiting at least five hours after inhalation to drive, and longer after consuming edibles.


Cultivation of adult-use cannabis on private property for personal use remains illegal. However, medical patients can cultivate six (6) plants and have eight (8) ounces of usable marijuana in the home. A healthcare practitioner may authorize patients to have up to 15 plants or up to 16 ounces of usable marijuana produced from their plants.


How Old Do I Need
to Be to Consume?
Possession Limit
for Flower
Possession Limit
for Concentrates

Medical Marijuana Registry

The Washington Legislature in 2015, passed SB 5052, the Cannabis Patient Protection Act (CPPA), establishing official state regulations for the production, possession, sale and use of medical marijuana. Medical cannabis patients are allowed to purchase up to three times the current limits for adult-use marijuana. Only cannabis patients in the authorization database, who hold medical marijuana identification cards, can purchase products free of sales and use taxes. Medical cards expire each year for adults, and every six months for minors, but some authorizing healthcare providers may specify an earlier expiration date.

Qualifying Conditions

  • Anorexia
  • Appetite loss
  • Cachexia, or wasting syndrome
  • Cancer
  • Chronic renal failure requiring hemodialysis
  • Crohn’s disease
  • Epilepsy or other seizure disorders
  • Glaucoma
  • Hepatitis C
  • Intractable pain
  • Multiple Sclerosis
  • Nausea
  • Post-traumatic stress disorder (PTSD)
  • Spasticity disorders
  • Traumatic brain injury


Petitions for adding more qualifying conditions ended after 2015. Only the Legislature can add eligible conditions.  


Mental health conditions such as bipolar disorder, severe depression and anxiety disorders do not qualify for medical cannabis use.

Application Process

  1. Patients with a qualifying condition may obtain a Medical Marijuana Authorization form to submit to  a health-care practitioner. Washington authorizes the following licensed medical professionals to evaluate patients for a medical marijuana recommendation:
  • Medical doctors (MD)
  • Physician assistants (PA)
  • Doctors of osteopathy (DO)
  • Osteopathic physician assistants (DOA)
  • Naturopathic physicians
  • Advanced registered nurse practitioners (ANRP)

   2. Patients must register with the Medical Marijuana Authorization database. A certified medical marijuana consultant can assist you. Consultant requirements are available here.

   3. Patients may be added to the database and receive their medical marijuana recognition card from any medically endorsed marijuana retailer in Washington.

Designated Providers

  1. Patients younger than 18 and adult medical patients can select a designated provider they authorize to purchase marijuana or grow it for them. Designated providers must:
    1. Be 21 years of age.
    2. Be named on the patient’s medical marijuana authorization form.
    3. Complete the form and sign on tamper-resistant paper.
    4. Be entered into the medical marijuana database.
    5. Be the minor’s parent or guardian.
  2. Receive a designated provider recognition card, if the patient chooses to be entered into the database.

Lab Testing

All marijuana grown and processed in Washington must be tested by a third-party lab testing facility in a multi-step process.


Certified labs must be certified in the following tests by the WSLCB:

  • Potency analysis
  • Microbial analysis
  • Pesticides
  • Terpenes
  • Moisture
  • Foreign matter screening
  • Microbiological screening
  • Mycotoxin screening
  • Residual solvent screening
  • Heavy metal screening


Information on this page was last verified on June 5, 2019. This page was last updated on June 14, 2019.