901 Mercer St, Seattle, WA 98109

Office · Seattle · Seattle-Bellevue metro, WA

Imagery suggests: mid-rise office, appears multi-tenant. 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 AI estimate from public imagery; may be outdated.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 96% of office buildings in Seattle (median 20,410 SF), derived from assessor records.

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Building size: 593,200 SF, King County Assessor
Lot size: 27,457 SF, King County Assessor
Year built: 2013, King County Assessor
Stories: 6, King County Assessor
Buildings on parcel: 2, King County Assessor
Predominant use: Amazon Phase Vi - South Building, King County Assessor
Assessed value: $85,811,000, per the King County Assessor (not a market appraisal)
Assessed value per building SF: $144.66/SF, derived from assessor records
Lot coverage: 2160%, derived from assessor records
Vintage: 2010s vintage
Zoning: SM-SLU 175/85-280, King County
County use code: Office Building
Construction (observed): steel glass, AI estimate from public imagery
Parking (observed): street only, AI estimate from public imagery
Frontage (observed): mid block, AI estimate from public imagery

Nearby comparable buildings

Same building type, by distance. Assessor facts only; not an opinion of value.

530 Westlake Ave N, Seattle · 0 mi · 512,665 SF · built 2021 · assessed $235.36/SF
850 Republican St, Seattle · 0.1 mi · 102,235 SF · built 1963 · assessed $819.64/SF
601 Westlake Ave N, Seattle · 0.1 mi · 356,410 SF · built 2015 · assessed $545.41/SF
960 Republican St, Seattle · 0.1 mi · 60,375 SF · built 1928 · assessed $738.22/SF
535 Terry Ave N, Seattle · 0.1 mi · 184,482 SF · built 2009 · assessed $230.02/SF
850 Republican St, Seattle · 0.1 mi · 436,497 SF · built 2008 · assessed $577.43/SF

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Sale history and market context

MakeMe Estimate: $76,322,454 (estimated market value), with a likely range of $68,976,580 to $99,444,545 (half of recent verified sales in this segment landed inside that range). Based on 12 verified arm's-length comparable sales (through 2026-05-29). Not an appraisal. How this estimate works.

Current ownership dates to 2015 (about 11 years) per recorded transfers.

2015-12-18: $298,856,963 from City Place VI LLC to Union Investment Real Estate GMBH (part of a 2-parcel sale; price is the whole deal), rec. 20151218000742

4 administrative transfers (no consideration), 2009 to 2013

2003-10-01: $21,250,000 from Marilyn Green LLC+Union Community LLC to City Investors XX LLC (part of a 2-parcel sale; price is the whole deal), rec. 20031001001155

2 administrative transfers (no consideration), 1986 to 2003

Source: King County recorded sales extract; buyer and seller shown only when a company or organization. Individual names are withheld.

Value over time

Solid line: county appraised value per King County tax rolls. Shaded range: our modeled estimate for each year, built from recorded arm's-length sales in the building's segment; years without enough sales stay unmodeled. Dots: recorded arm's-length sales. Not an appraisal. How this estimate works.

Land, site, and value history

Assessed value moved from $10,790,600 (2011) to $85,811,000 (2026), up 695% over 15 years, per county tax rolls. The 2026 roll splits $85,811,000 into $26,084,100 land and $59,726,900 improvements.

Zoning: SM-SLU 175/85-280 (per King County)

Lot: 27,457 sq ft

Water: Water District (per King County)

Sewer: Public (per King County)

Access: Public

Street surface: Paved

Floor and use mix: Office Building 395,722 SF; Parking Structure 111,000 SF; Underground Parking Structure 68,000 SF; Retail Store 18,478 SF (county building sections)

County districts report (schools, fire, sewer, council; on kingcounty.gov)

Permit history

2025-05-15: Remodel, declared value $180,000 (Screened), permit 7085537-CN

2025-02-21: Remodel, declared value $10,000 (Screened), permit 7071114-CN

2018-01-21: Remodel, declared value $524,400 (Screened), permit 6601435

2017-05-24: Remodel, declared value $375,000 (Screened), permit 6585833

2017-01-06: Remodel, declared value $125,000 (Screened), permit 6574967

2016-04-14: Remodel, declared value $405,832 (Screened), permit 6504453

2015-11-02: Remodel, declared value $198,000 (Screened), permit 6479362

2014-05-05: Remodel, declared value $1,500,000 (Complete), permit 6391864

2014-05-05: Remodel, declared value $500,000 (Complete), permit 6400309

2014-05-02: Remodel, declared value $2,000,000 (Complete), permit 6391862

Source: King County permit records (newest first).