Cannabis is legal for adults in Washington, but legalization doesn’t mean there are no restrictions. State law controls how much cannabis adults can possess, where it can be used, whether it can be grown at home, how it can be shared with another person, and when cannabis use can lead to criminal charges.
For someone facing a cannabis-related arrest or citation in Spokane, the distinction between legal and illegal conduct can come down to details such as the amount possessed, where the cannabis was located, whether money changed hands, or whether the person was driving.
Here are five important things to know about Washington marijuana laws and how they apply today.
Key Takeaways About Washington Cannabis Laws
- Adults 21 and older may legally possess cannabis within Washington’s statutory limits.
- Recreational cannabis generally can’t be consumed in public.
- Washington does not allow recreational home growing.
- Adults may give limited amounts of cannabis to another adult 21 or older without payment.
- A driver can be charged with marijuana DUI even when THC is below 5 ng/mL if other evidence shows impairment.
- Cannabis can’t legally be transported across state lines, even into another state where recreational cannabis is legal.
- Possessing more than the lawful amount or illegally selling or distributing cannabis can result in criminal charges.
1. Where Can You Legally Use Marijuana in Washington State?
Washington allows adults 21 and older to possess and consume cannabis, but public consumption remains illegal.
Under RCW 69.50.445, a person may not open a package containing cannabis or consume cannabis in view of the general public or in a public place.
- Streets and sidewalks
- Public parks and trails
- Bars and restaurants
- Public transportation areas
- Other places generally accessible to the public
Violating Washington’s public cannabis-use law is a Class 3 civil infraction.
Smoking and vaping cannabis are also subject to Washington’s restrictions on smoking in public places and workplaces.
Can You Smoke Marijuana on Private Property in Washington?
Generally, an adult 21 or older may consume cannabis on private property when the property owner permits it.
That doesn’t mean every private residence is automatically cannabis-friendly. A landlord, apartment complex, hotel, or other property owner can establish rules prohibiting cannabis use on the property. Medical authorization doesn’t necessarily override those property restrictions.
Federal law also continues to prohibit marijuana. Possessing or using cannabis on federal property, including certain federal buildings, military installations, and national parks, can therefore create legal problems even though the conduct might otherwise be lawful under Washington law.
2. Can You Grow Marijuana at Home in Washington?
Not for recreational use.
Washington remains one of the states that permits recreational cannabis possession but doesn’t generally allow adults to grow recreational marijuana at home. Growing cannabis without the required legal authority can expose a person to criminal charges.
Medical cannabis patients have different rules.
Under RCW 69.51A.210, a qualifying patient or designated provider with medical authorization who hasn’t entered the state’s medical cannabis authorization database may generally grow up to four plants at their domicile for the patient’s personal medical use. The statute also permits possession of up to six ounces of usable cannabis produced from those plants.
A patient or designated provider entered into the database may generally grow up to six plants and possess up to eight ounces produced from those plants.
When a healthcare professional determines that a patient’s medical needs require more, the authorization may permit the patient to grow up to 15 plants and possess up to 16 ounces of usable cannabis produced from those plants.
The number of plants permitted depends on the patient’s authorization and database status, so medical cannabis patients should understand exactly what their documentation permits before growing at home.
3. Can You Get a DUI for Marijuana in Washington?
Yes. Cannabis DUI is prosecuted under the same Washington DUI statute that applies to alcohol and other drugs.
Under RCW 46.61.502, a driver age 21 or older can be charged with DUI if a blood test shows a THC concentration of 5.00 nanograms per milliliter or higher within two hours after driving.
But there’s an important point that often causes confusion:
You can still be charged with marijuana DUI below 5 ng/mL.
The five-nanogram threshold isn’t a guarantee that someone below that number is legally safe to drive. Washington law separately allows a DUI prosecution when a person drives while under the influence of or affected by cannabis, regardless of whether the blood THC result reaches 5 ng/mL.
That means prosecutors may rely on other evidence, including observations of driving, physical behavior, statements made to officers, field sobriety testing, or blood-test results.
This distinction can be especially important in Washington marijuana DUI cases, because THC levels don’t necessarily correspond to impairment in the same predictable way that blood alcohol concentration is commonly used in alcohol DUI cases.
There is also no universal number of hours after consuming cannabis that guarantees a person is safe to drive. Effects vary depending on dosage, method of consumption, frequency of use, individual physiology, and other factors. Edible cannabis can also produce effects on a different timeline than inhaled cannabis.
If cannabis may still be affecting your ability to drive, don’t drive.
What Is the Marijuana DUI Limit for Drivers Under 21?
Washington has a separate law for drivers under 21. Under RCW 46.61.503, a driver under 21 can face an underage cannabis-driving offense when a blood test shows a THC concentration above 0.00 but below 5.00 ng/mL within two hours of driving. A THC concentration of 5.00 ng/mL or higher may instead support prosecution under Washington’s regular DUI statute.
Anyone arrested for a cannabis-related DUI should speak with an experienced Spokane DUI attorney before assuming that a blood-test number determines the outcome of the case. The circumstances surrounding the traffic stop, blood draw, testing process, alleged impairment, and other evidence can all matter.
4. How Much Marijuana Can You Legally Buy and Possess in Washington?
Washington law permits adults 21 and older to possess cannabis, but only within specific limits.
Under RCW 69.50.360, a licensed Washington cannabis retailer may sell an adult 21 or older up to:
- 1 ounce of usable cannabis
- 16 ounces of cannabis-infused product in solid form
- 72 ounces of cannabis-infused product in liquid form
- 7 grams of cannabis concentrate
Washington also created a separate category for certain low-THC cannabis-infused beverages packaged in individual units containing no more than four milligrams of THC. For qualifying products in that category, the daily retail limit is based on THC content rather than fluid ounces and may reach 200 milligrams of THC.
Adults should also understand that being allowed to purchase cannabis doesn’t authorize unlimited possession.
What Happens If You Have More Than the Legal Amount of Marijuana?
Possessing more cannabis than Washington law authorizes can lead to a criminal charge. Under RCW 69.50.4014, unauthorized knowing possession of 40 grams or less of cannabis is a misdemeanor.
Cases involving larger amounts can raise additional issues, and evidence suggesting that cannabis was intended for sale or distribution can potentially result in more serious allegations under Washington controlled substances laws.
A large amount alone is not the only fact prosecutors may consider. Packaging, cash, messages, scales, statements, and other circumstances may be used when law enforcement alleges possession with intent to distribute.
If you’re accused of possessing or distributing cannabis outside Washington’s legal framework, an attorney experienced with Washington drug charges can review exactly what the state must prove.
5. Can You Give Marijuana to Someone Else in Washington?
Yes, in limited circumstances.
Older summaries of Washington marijuana law sometimes state that adults can’t legally give cannabis to another person unless they’re a licensed retailer. That is no longer accurate.
Under RCW 69.50.4013, an adult 21 or older may give cannabis to another adult 21 or older for noncommercial purposes as long as the transaction isn’t conditioned on receiving money or other financial consideration.
- ½ ounce of usable cannabis
- 8 ounces of cannabis-infused product in solid form
- 36 ounces of cannabis-infused product in liquid form, subject to the rules for low-THC individually packaged beverages
- 3.5 grams of cannabis concentrate
- Up to 100 milligrams of THC in qualifying low-THC individually packaged cannabis beverages
The transfer must also satisfy statutory requirements concerning where or how the cannabis is transferred. For example, it can be given outside public view in a nonpublic place, or the product can remain in its original retail packaging.
Can You Sell Marijuana to Another Person?
That’s different. Giving a lawful amount of cannabis to another adult without receiving compensation doesn’t authorize an unlicensed person to operate a cannabis business.
Washington tightly regulates the manufacture, distribution, and sale of cannabis. Selling cannabis or possessing it with intent to unlawfully deliver it may result in criminal prosecution under RCW 69.50.401.
The distinction between a lawful gift and an unlawful sale can therefore be important.
Can You Have an Open Marijuana Package in Your Car?
Washington restricts how cannabis can be transported in a vehicle.
Under RCW 46.61.745, cannabis in a motor vehicle on a highway generally needs to be:
- In the trunk;
- In another area not normally occupied or directly accessible by the driver or passengers when the vehicle does not have a trunk; or
- In an unopened package or container whose seal has not been broken and contents have not been partially removed.
A glove compartment or utility compartment doesn’t qualify as an inaccessible area under the statute.
Consuming cannabis in a motor vehicle on a public highway is also prohibited.
Can You Take Marijuana From Washington to Another State?
No.
Washington legalization doesn’t authorize interstate transportation of cannabis.
Taking marijuana across state lines can violate federal law, even when you’re traveling from Washington to another state that has also legalized recreational cannabis. The same concern applies when crossing the Canadian border.
Legal in Washington doesn’t mean legal to transport everywhere else.
Frequently Asked Questions About Washington Marijuana Laws
Is marijuana legal in Washington State?
Yes. Adults age 21 and older may legally purchase and possess cannabis within Washington statutory limits. However, public consumption, recreational home growing, impaired driving, unauthorized sales, and possession beyond authorized amounts remain restricted.
Can you smoke marijuana anywhere in Washington?
No. Washington prohibits opening or consuming cannabis in public places or in view of the general public. Private property owners may also prohibit cannabis consumption on their property.
Can I grow marijuana for myself in Washington?
Not simply because you’re 21 or older. Washington doesn’t currently authorize recreational home cultivation. Qualifying medical cannabis patients and designated providers may grow plants when they meet the requirements of Washington medical cannabis laws.
Is 5 ng/mL the legal marijuana DUI limit in Washington?
For drivers 21 and older, a THC concentration of 5.00 ng/mL or higher within two hours after driving provides one statutory basis for DUI. However, a driver can also be convicted below 5 ng/mL if the state proves that the driver was under the influence of or affected by cannabis.
Can I give marijuana to a friend?
An adult 21 or older may give limited quantities of cannabis to another adult 21 or older without payment when the transfer complies with RCW 69.50.4013. Selling cannabis without the required license is different and can lead to criminal charges.
Is marijuana legal in a car in Washington?
Cannabis may be transported in a vehicle, but Washington regulates where it can be kept and whether the package may be open. Cannabis kept in the passenger area generally needs to remain in an unopened, sealed container. Open cannabis can generally be transported in the trunk or another legally permitted inaccessible area.
Charged With a Marijuana-Related Offense in Spokane?
Washington’s legalization laws protect specific conduct. They don’t prevent arrests or criminal charges when police believe someone exceeded possession limits, unlawfully distributed cannabis, grew it without authorization, or drove while impaired.
Those distinctions matter.
Christopher Bugbee began his career as a Spokane County prosecutor before moving into criminal defense. That experience provides perspective from both sides of a criminal prosecution when evaluating the evidence, how the state may approach the case, and what defenses may be available.
If you’ve been arrested for a marijuana DUI or another cannabis-related offense in Spokane, contact Bugbee Law to discuss the circumstances of your case and the next steps available to you.
With a deep commitment to protecting his clients’ rights, Christopher Bugbee draws on 30 years of criminal law experience—both as a prosecutor and defense attorney. He’s earned top ratings from legal peers and clients alike on Avvo and is consistently ranked among the region’s top criminal defense attorneys.