Union Square is a

skyscraper A skyscraper is a tall continuously habitable building having multiple floors. Most modern sources define skyscrapers as being at least or in height, though there is no universally accepted definition, other than being very tall high-rise bui ...

complex at Sixth Avenue between Union and University Streets in

Downtown Seattle Downtown is the central business district of Seattle, Washington. It is fairly compact compared with other city centers on the U.S. West Coast due to its geographical situation, being hemmed in on the north and east by hills, on the west by ...

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

, adjacent to

Freeway Park Freeway Park, officially known as Jim Ellis Freeway Park, is an urban park in Seattle, Washington, United States, connecting the city's downtown to the Seattle Convention Center and First Hill. The park sits atop a section of Interstate 5 and ...

. It consists of two skyscrapers built in the 1980s and primarily used for office space. The entire complex features a 1,100-stall parking garage, a courtyard, a retail plaza spanning three stories and an underground pedestrian concourse that connects with the Fifth Avenue Theater and Rainier Square. Both structures were awarded

LEED Leadership in Energy and Environmental Design (LEED) is a Green building certification systems, green building certification program used worldwide. Developed by the non-profit U.S. Green Building Council (USGBC), it includes a set of rating ...

certification in 2009 and eventually received LEED Platinum certification 6 years later as a result of reduced annual energy consumption by 40 percent through recent renovations. The entire complex is currently managed by Washington Holdings, a real estate firm also known as Union Square LLC which is based in Seattle.

Buildings

One Union Square

One Union Square is an aluminum clad skyscraper consisting of 36 floors with 2 floors below ground. Construction of this class A office building was completed in 1981. It is the first office building in Seattle to house all life-support systems in one location. The architect of One Union Square was TRA.

Two Union Square

Construction on Two Union Square began in 1987 and was complete by 1989. When accounting for the tip of the flag pole, the building is the third-tallest building in the Seattle skyline. The Seattle-based architectural firm

NBBJ NBBJ is an American global architecture, planning and design firm with offices in Boston, Columbus, London, Los Angeles, New York, Portland, Pune, San Francisco, Seattle and Shanghai. NBBJ provides services in architecture, interiors, planning ...

designed the tower, which was dedicated on July 29, 1989. Two Union Square has 56 floors with of rentable space, and an underground concourse connecting to the Seattle Hilton Hotel, and shopping at Rainier Square. It is the first skyscraper to use 19,000 lbs/in.²

high-strength concrete Concrete is produced in a variety of compositions, finishes and performance characteristics to meet a wide range of needs. Mix design Modern concrete mix designs can be complex. The choice of a concrete mix depends on the need of the project ...

Tenants

* AB Berstein * Alston, Courtnage & Bassetti LLP * Apex Companies, LLC *

Apple, Inc. Apple Inc. is an American multinational corporation and technology company headquartered in Cupertino, California, in Silicon Valley. It is best known for its consumer electronics, software, and services. Founded in 1976 as Apple Computer Com ...

* AmWins * Arboretum Mortgage * Avenue 55 * BDO * Bennett, Bigelow & Leedom P.S. * BlackRock Financial * Bush Strout & Kornfeld * Chapter 13 Trustee * Colliers International * Ederer Investment Company * Edge Asset Management * First Choice Health * Flinn Ferguson * Floyd, Snider * Frazier Healthcare * Gordon, Tilden, Thomas, Cordell * GreaterGood Network * HDR, Inc. * Homestreet Bank * Horizon Realty Advisors, LLC * Integra Realty Resources * Jones Lang LaSalle * Kidder Mathews * Kosmos Management * Lasher Holzapfel Sperry & Ebberson * LBA Realty * Littler Mendelson, PC * Lockton * The Lyman Group * Marcus & Millichap * McNaul, Ebel, Hawrot & Nelgren PLLC *

Morgan Stanley Wealth Management Morgan Stanley Wealth Management is an American Multinational corporation, multinational financial services corporation specializing in Broker, retail brokerage. It is the wealth & asset management division of Morgan Stanley. On January 13, 2009, ...

* National Center for APEC * Northwestern Mutual Financial Network * Pacific Project Management (PPM) * Paragon Real Estate Advisors * Penrith Home Loans * Pillar International Insurance Advisors * Porter Foster Rorick LLP *

Protiviti Protiviti Inc. (Protiviti) is a global consulting firm headquartered in Menlo Park and San Ramon, California, that provides consulting in internal audit, risk and compliance, technology, business processes, data analytics and finance. It is a ...

* Robert A. Underhill *

Robert Half International Robert Half Inc. is an international human resource consulting firm founded in 1948, based in Menlo Park, California, Menlo Park and San Ramon, California. It is among the world's largest accounting and finance staffing firms, with over 345 loca ...

* Sashen Ventures * Seattle Chamber Music * Stoel Rives LLP *

Taipei Economic and Cultural Office in Seattle The Taipei Economic and Cultural Representative Office in the United States () represents the interests of Taiwan in the United States in the absence of formal diplomatic relations, functioning as a ''de facto'' embassy. Its counterpart in Taiw ...

* USI Insurance Services Northwest *

Wedbush Securities Wedbush Securities Inc. is a privately held financial services firm based in Los Angeles. As of April 2025, the firm had $5.7 billion under management with 10,099 clients. Wedbush operates three divisions: Wealth Management, Investment Banking ...

Williams Kastner Williams Kastner is a law firm headquartered in the Two Union Square building in Seattle, Washington. The firm is ranked number 10 on the list of the Puget Sound area's largest law firms by the Puget Sound Business Journal. Overview William ...

Willis Towers Watson Willis Towers Watson plc, branded as WTW and stylised in its logo as wtw, is a British-American multinational company that provides commercial insurance brokerage services, strategic risk management services (such as contingency planning, sec ...

References

External links

Union Square official websiteSeattle Virtual tour
at Bohonus VR Photography {{Seattle Skyscrapers NBBJ buildings Skyscraper office buildings in Seattle Twin towers Buildings and structures in Downtown Seattle Office buildings completed in 1981 Office buildings completed in 1989 1989 establishments in Washington (state)