Washington law does not generally prohibit the open carry of firearms in public places, but does regulate the locations where firearms and other weapons may be possessed.

It is a gross misdemeanor for a person who knowingly possesses a weapon to enter certain locations.  Weapons are prohibited in restricted areas of jails, public mental health facilities, commercial airports, courtrooms and other areas used in connection with court proceedings, and in places classified as off-limits to persons under 21 years of age by the Washington State Liquor and Cannabis Board.  The perimeter of any location where weapons are prohibited must be posted at reasonable intervals to alert the public that firearms are prohibited at the location.  Law enforcement personnel, and military and security personnel, while engaged in official business, are exempt from these restrictions and a number of other exceptions apply.
 
"Weapon" is defined as a firearm, explosive, or an instrument or weapon listed in another statute governing dangerous weapons.  The dangerous weapon statute prohibits:  (a) the possession of slung shots, sand clubs, metal knuckles, spring blade knives, and knives that open by a spring mechanism or by the force of gravity or a downward or outward thrust; (b) the furtive carrying, with intent to conceal, any dagger, dirk, pistol, or other dangerous weapon; and (c) the use of any device for suppressing the noise of a firearm.
 
With several exceptions, it is also a gross misdemeanor offense for a person to possess firearms or weapons on public or private elementary or secondary school premises, school-provided transportation, or areas of facilities that are being used exclusively by public or private schools.  Prohibited weapons include:  nun-chu-ka sticks; throwing stars; air guns; stun guns; devices intended to injure a person with an electric shock, charge, or impulse; and weapons listed under the dangerous weapons statute.  Elementary and secondary schools are required to post "GUN-FREE ZONE" signs providing notice that firearms are prohibited on school premises.
 
A person is prohibited from carrying a loaded pistol in a vehicle unless the person has a concealed pistol license and either:  the pistol is on the licensee's person; the licensee is within the vehicle at all times the pistol is present; or the licensee is away from the vehicle and the pistol is locked within the vehicle and concealed from view.  An unloaded pistol kept in a vehicle must be locked within the vehicle and concealed from view.  In addition, it is generally unlawful to possess or transport a loaded rifle or shotgun in or on a motor vehicle.

Restrictions on the open carry of firearms and other weapons are established with respect to permitted demonstrations, as well as state capitol grounds and buildings, and legislative facilities.
 
It is unlawful for a person to openly carry a firearm or other weapon:

• at any permitted demonstration, whether the person carries the firearm or other weapon on his or her person or in a vehicle;
• within 250 feet of a permitted demonstration after a law enforcement officer advises the person of the permitted demonstration and directs the person to leave until he or she no longer possesses or controls the firearm or other weapon, except this prohibition does not apply to a person possessing or controlling a firearm or other weapon on private property owned or leased by that person; or
• on the West State Capitol Campus grounds, in any buildings on the state capitol grounds, in any state legislative office, or at any location of a public legislative hearing or meeting during the hearing or meeting.

 
A violation is a gross misdemeanor offense.  Exemptions are provided for:  federal, state, and local law enforcement officers and personnel when carrying a firearm or weapon in conformance with their employing agency's policy; and members of the armed forces of the United States or the state of Washington when carrying a firearm or other weapon in the discharge of official duty or traveling to or from official duty.
 
"Permitted demonstration" means either:

• a gathering for which a permit has been issued by a federal or state agency or a local government; or
• a gathering of 15 or more people who are assembled for a single event at a public place, including a march, rally, vigil, sit-in, or picketing, which has been declared as permitted by the chief executive, sheriff, or chief of police of a local government in which the gathering occurs.

 
"Public place" means any site accessible to the general public for business, entertainment, or other lawful purpose, including:  the front, immediate area, or parking lot of any store, shop, restaurant, tavern, shopping center, or other place of business; any public building, its grounds, or surrounding area; or any public parking lot, street, right-of-way, sidewalk, public park, or other public grounds.

"Buildings on the state capitol grounds" is defined as specifically listed buildings located on the state capitol grounds.