520 WESTLAKE AVE N
Office · Seattle · 98109
At a glance
520 WESTLAKE AVE N in Seattle, WA is listed on the Seattle / King County property roll as “Office”, parcel (major-minor) 1983200180. The roll records 512,665 sq ft of building area, 12 floors, a 2021 build year and an assessed value of $120,660,000. It last sold for $50,000 in Jan 2020 on a deed covering 2 parcels. 2 active business locations at this address appear in public records.
The building's own benchmarking filing
Energy performance
From the building's own filing under its city's benchmarking ordinance. An ENERGY STAR score of 75 or above means the building outperforms three quarters of comparable buildings nationally. It is a self-reported figure, verified by the city only to the extent the ordinance requires.
Recorded transfers — county roll + state sale file
Sale history
The most recent transfer covered 2 parcels. The price shown is the whole transaction, not this parcel alone, so any per-square-foot figure is measured across everything the deed conveyed. The county record carries no multi-parcel flag for it; the parcels were identified by their identical price, date and ZIP.
| Recorded | Price | Qualification | Source | Instrument |
|---|---|---|---|---|
| Jan 2020 | $50,000 | not rated | County roll | — |
| Sep 2019 | $746,699 | not rated | County roll | — |
Prices are the consideration recorded in Seattle / King County's public property records. Where a qualification code exists it is the assessor's judgement of whether a transfer was arm's length; transfers without one appear unrated rather than assumed clean. Whether a building is on the market today, and at what price, is not a public record and is not shown here — asking prices, listings and lease terms live in private commercial databases.
Public record — 2 matched business locations
Tenants & business locations
| Company | Suite / floor | Since | Source | Match |
|---|---|---|---|---|
| RESTAURANT ASSOCIATES LLC 008 | — | Sep 2026 | Seattle business licence | address · medium |
| Ace Parking Management Incvia ACE PARKING MANAGEMENT INC | — | Jun 2023 | Seattle business licence | address · medium |
Seattle / King County assessment roll
Parcel record
| Field | Value |
|---|---|
| parcel (major-minor) | 1983200180 |
| Site address | 520 WESTLAKE AVE N |
| Land use (DOR) | — Office |
| Building area (actual) | 512,665 sq ft |
| Floors / units / buildings | 12 / — / 1 |
| Lot size | — |
| Year built | 2021 |
| Zoning (primary) | — |
| Land value | $23,379,500 |
| Building value | — |
| Total assessed value | $120,660,000 |
Recorded owner (assessment roll)
No owning organisation shown. Where the county roll names a private individual, the name and mailing address are not published here.
Location
- Address
- 520 WESTLAKE AVE N
- City
- Seattle
- ZIP
- 98109
Within ~650 m
Nearby office buildings
No other office parcels within ~650 m.
How does 520 WESTLAKE AVE N compare with other Seattle office buildings?
At 512,665 sq ft, 520 WESTLAKE AVE N is about 11 times the size of the average office building on the Seattle / King County roll, which comes to 46,649 sq ft across 4,289 buildings.
With 12 floors it is one of 116 office buildings of ten or more floors in the metro.
Its assessed value works out to $235 per square foot of building area, against $230 across all office floor area on the roll.
The last recorded sale priced it at $0 per square foot across the parcels conveyed.
Does the owner of 520 WESTLAKE AVE N hold other Seattle office property?
Seattle / King County's published roll does not include owner names, so no owner is shown for any parcel in this metro.
What has happened at 520 WESTLAKE AVE N recently?
2 recorded transfers are on file for this parcel, the latest dated Jan 2020.
The building files energy-benchmarking disclosures — 1 report year are matched to this parcel.
What does “Office” mean for this parcel?
The Seattle / King County roll classifies parcel (major-minor) 1983200180 as “Office”. BuildingCensus includes a parcel in its office census when the roll gives it an office-class use, so the label is the county's, not an inference.
Frequently asked questions
Who owns 520 WESTLAKE AVE N?
Seattle / King County's published roll does not include owner names, so no owner is shown.
What companies have offices at 520 WESTLAKE AVE N?
2 active business locations at this building appear in Seattle / King County public records, including RESTAURANT ASSOCIATES LLC 008, Ace Parking Management Inc. Public records under-count tenants that don't hold a local receipt or register the address.
How big is 520 WESTLAKE AVE N?
The Seattle / King County roll records 512,665 sq ft of building area, 12 floors, a build year of 2021.
What is the assessed value of 520 WESTLAKE AVE N?
$120,660,000 on the Seattle / King County roll. Assessed values are taxable-roll figures, not market prices.
When did 520 WESTLAKE AVE N last sell?
The last recorded transfer was in Jan 2020 for $50,000, on one deed conveying 2 parcels ($0 per square foot).
What is the parcel (major-minor) for 520 WESTLAKE AVE N?
Parcel (major-minor) 1983200180, site address 520 WESTLAKE AVE N, Seattle. It is the key to look the parcel up in the King County Assessor bulk extracts and Seattle open data (Seattle / King County).
More around 520 WESTLAKE AVE N
Everything here comes from public records, and public records go stale. If you know better, say so.
Data provenance — public records only
- Seattle / King County — King County Assessor bulk extracts and Seattle open data. Washington law restricts commercial use of lists of individuals, so this metro is built without personal names by design: the county's name-stripped account file provides mailing addresses (portfolios group by mailing cluster, unnamed), sales show price and date but never buyer or seller, and tenants are business licence trade names.
Every fact on this page is drawn from the government records above — no listing sites, no scraped platforms, no third-party images. Facts from public records are uncopyrightable; each tenancy row carries its source and match confidence. Records can lag reality — a business-tax receipt or registration at an address is evidence of occupancy, not a lease confirmation.
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Dataset updated . Source: Seattle / King County assessment roll, parcel (major-minor) 1983200180.
About this data
Source: King County Assessor bulk extracts and Seattle open data (Seattle / King County), as published September 20, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “520 WESTLAKE AVE N, Seattle, WA (parcel (major-minor) 1983200180)”, https://buildingcensus.com/offices/seattle/office-building-e4e1e79f (data as of September 20, 2026).