Legislation History

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


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


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


I-502 legalized recreational 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?

Recreational cannabis may only be legally purchased from a state-licensed retailer. Patients and caregivers may also purchase medical cannabis from any state-licensed retailer.


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 public. It is also prohibited to smoke cannabis 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 L, in liquid form; and 7 grams, or a quarter-ounce (0.25 oz), of cannabis concentrates.


Medical patients may purchase and possess 3 ounces of usable marijuana, 48 ounces of marijuana-infused product in solid form, 216 ounces of marijuana-infused product in liquid form, or 21 grams of marijuana concentrate.


Driving under the influence of cannabis is illegal and consumption in a vehicle is not allowed, neither while driving nor while riding as passengers. Legal 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.


Cultivation of recreational cannabis on private property for personal use remains illegal.


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

Medical Marijuana Registry

In 2015, the Washington Legislature passed SB 5052, the Cannabis Patients 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 recreational adult-use marijuana. Only cannabis patients in the authorization database, who have medical marijuana ID cards can purchase products free of sales and use taxes. Medical cards expire each year for adults, six months for minors, but some authorizing healthcare providers may specify an earlier expiration date.

Qualifying Conditions

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

Application Process

  1. Patients with a qualifying condition may obtain a Medical Marijuana Authorization from a healthcare practitioner.
  2. Patients must register with the Medical Marijuana Authorization database by seeing a certified medical marijuana consultant.
  3. Patients may be added to the database and receive their medical marijuana recognition card from any medically endorsed marijuana retailer in Washington.


The law allows for non-residents who have a valid driver’s license, state or federal ID to purchase marijuana for recreational use.

Lab Testing

All marijuana grown and processed in the State of Washington must be tested by a third-party lab testing center.


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

  • Potency analysis [THCA/CBDA]
  • Moisture analysis
  • Foreign matter screening
  • Microbiological screening
  • Mycotoxin screening
  • Residual solvent screening
  • Heavy metal screening

This page was last updated on May 17, 2018.