601 Union St, Seattle, WA 98101
Office · Seattle · Seattle-Bellevue metro, WA
Imagery suggests: parking garage. AI estimate from public imagery. In recent public imagery (2026-06), the building appears well maintained. AI estimate from public imagery; may be outdated.
One of 957 reachable office buildings in Seattle. Larger than 100% of office buildings in Seattle (median 20,410 SF), derived from assessor records.
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Claim or manage this building- Building size
- 1,607,844 SF, King County Assessor
- Lot size
- 89,950 SF, King County Assessor
- Year built
- 1989, King County Assessor
- Stories
- 56, King County Assessor
- Predominant use
- Two Union, King County Assessor
- Assessed value
- $365,997,600, per the King County Assessor (not a market appraisal)
- Assessed value per building SF
- $227.63/SF, derived from assessor records
- Lot coverage
- 1787%, derived from assessor records
- Vintage
- 1980s vintage
- Zoning
- DOC1 U/450/U, King County
- County use code
- Office Building
- Construction (observed)
- masonry, AI estimate from public imagery
- Parking (observed)
- structured, AI estimate from public imagery
Nearby comparable buildings
Same building type, by distance. Assessor facts only; not an opinion of value.
- 600 University St, Seattle · 0 mi · 796,463 SF · built 1980 · assessed $221.65/SF
- 1200 6th Ave, Seattle · 0.1 mi · 457,439 SF · built 1971 · assessed $174/SF
- 1400 5th Ave, Seattle · 0.1 mi · 135,864 SF · built 1958 · assessed $175.55/SF
- 1420 5th Ave, Seattle · 0.1 mi · 1,545,072 SF · built 1989 · assessed $162.56/SF
- 520 Pike St, Seattle · 0.1 mi · 505,528 SF · built 1983 · assessed $213.91/SF
- 425 Pike St, Seattle · 0.1 mi · 109,830 SF · built 1984 · assessed $284.81/SF
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