100 4th Ave N, Seattle, WA 98109

Office · Seattle · Seattle-Bellevue metro, WA

Imagery suggests: modern office tower, 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 AI estimate from public imagery; may be outdated.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 85% of office buildings in Seattle (median 20,410 SF), derived from assessor records.

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Building size: 213,834 SF, King County Assessor
Lot size: 42,454 SF, King County Assessor
Year built: 2001, King County Assessor
Stories: 6, King County Assessor
Predominant use: Komo Plaza - West Building, King County Assessor
Assessed value: $89,588,000, per the King County Assessor (not a market appraisal)
Assessed value per building SF: $418.96/SF, derived from assessor records
Lot coverage: 504%, derived from assessor records
Vintage: 2000s vintage
Zoning: SM-UP 160 (M), King County
County use code: Office Building
Construction (observed): steel glass, AI estimate from public imagery
Parking (observed): none visible, AI estimate from public imagery

Nearby comparable buildings

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

140 4th Ave N, Seattle · 0 mi · 378,443 SF · built 2001 · assessed $368.63/SF
222 5th Ave N, Seattle · 0.1 mi · 228,118 SF · built 2023 · assessed $731.39/SF
2901 3rd Ave, Seattle · 0.2 mi · 396,626 SF · built 1982 · assessed $129.36/SF
120 6th Ave N, Seattle · 0.2 mi · 51,552 SF · built 2013 · assessed $265.99/SF
401 5th Ave N, Seattle · 0.2 mi · 1,803 SF · built 1965
2401 4th Ave, Seattle · 0.2 mi · 234,000 SF · built 1978 · assessed $144.90/SF

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Sale history and market context

MakeMe Estimate: $85,381,885 (estimated market value), with a likely range of $77,164,061 to $111,248,556 (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 2016 (about 10 years) per recorded transfers.

2016-12-20: $275,833,563 from Hines Global REIT 100/140 Fourth Ave LLC to Gi TC Seattle LLC (part of a 2-parcel sale; price is the whole deal), rec. 20161221001938

2011-12-15: $159,400,000 from Fisher Media Services CO to Hines Global REIT 100/140 Fourth Ave LLC (part of a 2-parcel sale; price is the whole deal), rec. 20111215001454

2 administrative transfers (no consideration), 2001 to 2001

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 $28,317,100 (2011) to $89,588,000 (2026), up 216% over 15 years, per county tax rolls. The 2026 roll splits $89,588,000 into $33,963,200 land and $55,624,800 improvements.

Zoning: SM-UP 160 (M) (per King County)

Lot: 42,454 sq ft

Water: Water District (per King County)

Sewer: Public (per King County)

Access: Public

Street surface: Paved

Floor and use mix: Basement, Parking 104,922 SF; Computer Center 47,688 SF; Office Building 43,072 SF; Retail Store 18,152 SF (county building sections)

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

Permit history

2026-04-20: Remodel, declared value $101,504, permit 7122546-CN

2026-04-06: Electrical, permit 7137025-EL

2026-02-04: Other, declared value $1, permit 7126501-CN

2026-02-04: Electrical, permit 7127899-EL

2026-01-05: Electrical, permit 7123540-EL

2025-11-06: Electrical, declared value $1,000, permit 7115562-EL

2025-09-03: Electrical, declared value $12,920, permit 7104867-EL

2025-08-06: Electrical, declared value $11,760, permit 7100352-EL

2025-07-31: Electrical, declared value $55,000, permit 7099474-EL

2025-07-17: Electrical, declared value $3,000, permit 7096821-EL

Source: King County permit records (newest first).