4001 1st Ave S, Seattle, WA 98134

Small-Bay Industrial · Seattle · Seattle-Bellevue metro, WA

Imagery suggests: industrial flex, appears multi-tenant. AI estimate from public imagery. In recent public imagery (2026-06), the building appears serviceable with visible wear. AI estimate from public imagery; may be outdated.

One of 1,229 reachable small-bay industrial buildings in Seattle. Larger than 98% of small-bay industrial buildings in Seattle (median 14,469 SF), derived from assessor records.

Own this building?

Claim privately

Claiming is for you. Your mailing address is never shown; no offer reaches you unless you opt in.

Claimed owners can confirm facts, watch the estimate, and decide whether to reply.

Claim or manage this building

Building size: 188,681 SF, King County Assessor
Lot size: 295,308 SF, King County Assessor
Year built: 1946, King County Assessor
Stories: 1, King County Assessor
Predominant use: Business Park, King County Assessor
Assessed value: $52,800,000, per the King County Assessor (not a market appraisal)
Assessed value per building SF: $279.84/SF, derived from assessor records
Lot coverage: 64%, derived from assessor records
Vintage: 1940s vintage
Zoning: MML U/85, King County
County use code: Warehouse
Construction (observed): masonry, AI estimate from public imagery
Parking (observed): surface lot, AI estimate from public imagery

Nearby comparable buildings

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

3851 1st Ave S, Seattle · 0.1 mi · 35,579 SF · built 1998 · assessed $233.77/SF
4100 1st Ave S, Seattle · 0.1 mi · 22,324 SF · built 1941 · assessed $157.06/SF
4000 1st Ave S, Seattle · 0.1 mi · 56,608 SF · built 1940 · assessed $170.29/SF
3841 1st Ave S, Seattle · 0.1 mi · 10,320 SF · built 1941 · assessed $210.12/SF
130 S Dakota St, Seattle · 0.1 mi · 36,000 SF · built 1950 · assessed $144.46/SF
3847 1st Ave S, Seattle · 0.1 mi · 213,525 SF · built 2022 · assessed $264.87/SF

Want to talk to the owner? makeme1031 delivers a private, principal-to-principal letter to the owner of record. We never publish the owner's identity or address.

Sale history and market context

MakeMe Estimate: $56,863,418 (estimated market value), with a likely range of $49,034,875 to $63,438,854 (half of recent verified sales in this segment landed inside that range). Based on 96 verified arm's-length comparable sales (through 2026-05-29). Not an appraisal. How this estimate works.

Last sold: 2021-03-31 for $53,453,000 (recorded arm's-length sale).

Current ownership dates to 2021 (about 5 years) per recorded transfers.

2021-03-31: $53,453,000 from 4105 First Avenue South Investments LLC to Nicola Urbanworks LP, rec. 20210401000265

2008-03-18: $16,600,000 from Bit Holdings Sixty One INC to 4105 First Avenue South Investments LLC, rec. 20080319001488

2005-04-05: $11,836,281 from Calwest Industrial Holdings LLC to Bit Holdings Sixty-One INC, rec. 20050407002226

2002-02-26: transfer from Calwest Industrial Properties LLC to Calwest Industrial Holdings LLC (part of a 30-parcel sale; price is the whole deal), rec. 20020301002215

2000-01-11: $11,500,400 from Spieker Properties #178 L P to Calwest Industrial Properties LLC, rec. 20000111001891

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 $15,403,400 (2011) to $52,800,000 (2026), up 243% over 15 years, per county tax rolls. The 2026 roll splits $52,800,000 into $22,148,100 land and $30,651,900 improvements.

Zoning: MML U/85 (per King County)

Lot: 295,308 sq ft

Water: Water District (per King County)

Sewer: Public (per King County)

Access: Public

Street surface: Paved

Floor and use mix: Warehouse, Distribution 148,689 SF; Warehouse Office 21,536 SF; Parking Levels (Intermediate/Under Building) 8,061 SF (county building sections)

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

Permit history

2026-02-09: Electrical, permit 7128597-EL

2025-12-09: Electrical, declared value $550, permit 7120366-EL

2025-11-20: Electrical, declared value $25,000, permit 7117790-EL

2025-08-08: Other, declared value $1,500, permit 7100601-RF

2025-07-07: Electrical, declared value $2,000, permit 7094825-EL

2025-05-21: Other, declared value $1,000 (Screened), permit 7087168-RF

2025-05-20: Electrical, declared value $1,000 (Complete), permit 7087041-EL

2025-04-25: Remodel, declared value $4,568,340 (Revisit), permit 7023799-CN

2024-10-02: Electrical, declared value $1,100 (Complete), permit 7049031-EL

2024-05-13: Other, declared value $13,456 (Complete), permit 7024638-RF

Source: King County permit records (newest first).