Currently based in Kirkland

• Amaze Entertainment
  Amaze Entertainment
  Amaze Entertainment was a video game developer from the United States that sold over 100 games in its ten-year history , for several video game platforms, with headquarters located in Kirkland, Washington. Amaze’s primary focus was licensed games based on movie franchises, comic series, and...
  
  
• ATG Stores
  ATG Stores
  ATG Stores is the trade name for Allied Trade Group, Inc., an e-commerce company which began in 1999 with the launch of its first website, Lighting Universe...
  
  
• bgC3
  BgC3
  bgC3 LLC is a company founded by Microsoft's co-founder, Bill Gates in 2008.The name is an acronym for Bill Gates Catalyst 3, with the appended number pointing to a third endeavor beyond Microsoft and the Bill & Melinda Gates Foundation.According to the company's federal trademark registration, it...
  
  
• Clearwire
  Clearwire
  Clearwire Corporation is a wireless internet service provider serving markets in the United States, Belgium, and Spain...
  
  
• Griptonite Games
  Griptonite Games
  Griptonite Games, is an American video game developer developer located in Kirkland, Washington. It is currently wholly owned by Glu Mobile, but was formerly a part of super-developer Foundation 9 Entertainment, where it was previously a studio of Amaze Entertainment.-History:Steve Ettinger opened...
  
  
• INRIX
  Inrix
  INRIX is a software company which provides a variety of mobile applications and Internet services pertaining to traffic and navigation. INRIX provides historical and real-time traffic information to businesses and individuals in over 30 countries including the United States and much of Europe...
  
  
• Kenworth
  Kenworth
  Kenworth is an American manufacturer of medium and heavy-duty Class 8 trucks based in Kirkland, Washington, United States, a suburb of Seattle. It is a subsidiary of PACCAR, and is also a former manufacturer of transit buses and school buses.-History:...
  
  
• Lancs Industries
  Lancs Industries
  Lancs Industries is a manufacturer of protective clothing, containments, gloveboxes, enclosures, lead shielding, and other supplies used for reducing risk and increasing safety of workers in potentially hazardous environments....
  
  
• LTC Financial Partners
  LTC Financial Partners
  LTC Financial Partners, LLC , based in Kirkland, Washington, is one of the largest long term care insurance agencies in the United States. Its field is one of growing importance as millions of Baby Boomers reach retirement age, and as health reform acknowledges the care needs of an aging population...
  
  
• Monolith Productions
  Monolith Productions
  Monolith Productions is a Kirkland, Washington-based computer game developer. Monolith is also known for the development of the graphical game engine Lithtech, which has been used for most of their games...
  
  
• Papillon Airways
  Papillon Airways
  Papillon Airways, founded 1965, is the mother company to Papillon Grand Canyon Helicopters. Originally started as Grand Canyon Helicopters, and later as Papillon Hawaiian Helicopters, the company is incorporated in Washington State...
  
  
• RAD Game Tools
  RAD Game Tools
  RAD Game Tools is privately held company owned by Jeff Roberts and Mitch Soule based in Kirkland, Washington that develops video and computer game software technologies which are licensed primarily by video game companies. RAD Game Tools is somewhat unusual among middleware companies as they...
  
  
• UIEvolution (formerly a subsidiary of Square-Enix).
• WaveDivision Holdings (parent company of Astound Broadband
  Astound Broadband
  Astound Broadband is a provider of cable TV, broadband internet, and telephone services on the American West Coast, with customers in communities in Sacramento, and the San Francisco Bay Area of California....
  
   and Wave Broadband
  Wave Broadband
  Wave Broadband is a leading provider of cable TV, broadband internet, and telephone services on the West Coast, serving customers in communities in Western Washington State, Oregon, Sacramento, and the San Francisco Bay Area....
  
  )

Formerly based in Kirkland

• Costco
  Costco
  Costco Wholesale Corporation is the largest membership warehouse club chain in the United States. it is the third largest retailer in the United States, where it originated, and the ninth largest in the world...
  
   (moved to Issaquah
  Issaquah, Washington
  Issaquah is a city in King County, Washington, United States. The population was 30,434 at the 2010 census.Based on per capita income, Issaquah ranks 25th of 522 areas in the State of Washington to be ranked....
  
  )
• Hale's Ales
  Hale's Ales
  -History:It was founded by Mike Hale in 1983. The first batch was brewed in a Colville, Washington apartment before the brewery opened in a local warehouse. Its second brewery opened four years later in Kirkland, Washington. The Colville brewery moved to Spokane, Washington, in 1992, and the...
  
   (moved to Ballard
  Ballard, Seattle, Washington
  Ballard is a neighborhood located in the northwestern part of Seattle, Washington. To the north it is bounded by Crown Hill, ; to the east by Greenwood, Phinney Ridge and Fremont ; to the south by the Lake Washington Ship Canal; and to the west by Puget Sound’s Shilshole Bay. The neighborhood’s...
  
  )
• Onyx Software (acquired by Consona Corporation
  Consona Corporation
  Consona Corporation is a software company delivering software solutions to automate business critical tasks, ranging from marketing, service and support to planning and scheduling, material requirements planning , accounting, product configuration, and business intelligence.-Company History:Consona...
  
  )
• Seattle Seahawks
  Seattle Seahawks
  The Seattle Seahawks are a professional American football team based in Seattle, Washington. They are currently members of the Western Division of the National Football Conference in the National Football League . The team joined the NFL in 1976 as an expansion team...
  
   (moved to Renton)
• Terabeam
  Terabeam
  Terabeam was a formerly Kirkland, Washington-based company that designed and manufactured free-space optical transceivers for Internet access in city downtowns. Through a series of acquisitions and reverse acquisitions in 2004, the company headquarters moved to San Jose, California and Terabeam...
  
   (moved to San Jose)
• Valve Corporation
  Valve Corporation
  Valve Corporation is an American video game development and digital distribution company based in Bellevue, Washington, United States...
  
   (moved to Bellevue)
• Bungie Studios (moved to Bellevue)

Defunct

• Cranky Pants Games
• Lake Washington Shipyard
  Lake Washington Shipyard
  Lake Washington Shipyards was a shipyard in Houghton, Washington on the shore of Lake Washington. Today the shipyards are the site of the lakeside Carillon Point business park...
  
  
• Lamonts
  Lamonts
  Lamonts was a chain of department stores founded in Seattle, Washington. The chain was started in 1970 when Pay 'n Save renamed its suburban branches of Rhodes, a department store chain the company acquired in 1965. Lamonts remained a division of Pay 'n Save until 1985...
  
  
• Teledesic
  Teledesic
  Teledesic was a company founded in the 1990s to build a commercial broadband satellite constellation for Internet services. Using low-earth orbiting satellites small antennas could be used to provide uplinks of as much as 100 Mbit/second and downlinks of up to 720 Mbit/second...
  
  
• Wall Data

Branches based in Kirkland

• IBM
  IBM
  International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
  
   (FileNet)
• Google
  Google
  Google Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...
  
   (Currently expanding to three 60000 sq ft (5,574.2 m²) concrete office buildings over a common parking garage of 170000 sq ft (15,793.5 m²), located in the Houghton area of Kirkland.)

• Microsoft
  Microsoft
  Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
  
  (located in the Parkplace Center area.)