810 3RD AVE
Office · Seattle · 98104
At a glance
810 3RD AVE in Seattle, WA is listed on the Seattle / King County property roll as “Office”, parcel (major-minor) 0942000550. The roll records 201,480 sq ft of building area, 8 floors, a 1907 build year and an assessed value of $31,969,000. It last sold for $67,500,000 in Jul 2018. 10 active business locations at this address appear in public records.
Derived from suite and floor strings in the occupancy records
Which floors show activity
Floors 4-5 show no business on record — 2 unbroken floors, the longest such stretch here. Also quiet: 7-8. That is where the public record shows nobody, in blocks — a place to start asking, not a listing.
- 8no record
- 7no record
- 62 on record
- 5no record
- 4no record
- 32 on record
- 24 on record
- 11 on record
Floors are read from suite numbers on Seattle / King County business records (suite 4900 → floor 49). A floor with no record is not necessarily vacant — it may be mechanical, occupied by the owner, or let to a business whose receipt carries no suite. Receipts also lag reality by months. This shows where the public record places businesses, not a rent roll or an availability report. A stretch of quiet floors is not contiguous space for rent — it is contiguous silence in the record, which is the closest thing the public record has to that question and worth exactly what it costs to check.
Recorded transfers — county roll + state sale file
Sale history
| Recorded | Price | Qualification | Source | Instrument |
|---|---|---|---|---|
| Jul 2018 | $67,500,000 | 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 — 10 matched business locations
Tenants & business locations
| Company | Suite / floor | Since | Source | Match |
|---|---|---|---|---|
| SYNECT LLC | # 324 | Jun 2021 | Seattle business licence | address · medium |
| SEXUAL VIOLENCE LAW CENTER | # 630 | Sep 2019 | Seattle business licence | address · medium |
| 7 ELEVEN 37068A | — | Nov 2016 | Seattle business licence | address · medium |
| NORTHWEST PROPERTY TAX CONSULTANTS | # 228 | Aug 2016 | Seattle business licence | address · medium |
| CH2M HILL INC | # STE 252 | Sep 2014 | Seattle business licence | address · medium |
| TELEOS | # 120 | Jul 2008 | Seattle business licence | address · medium |
| THE ADEE LAW FIRM PLLC | # 308 | Apr 2006 | Seattle business licence | address · medium |
| LAW OFFICES OF PATRICIA BOSTROM | # 258 | Jan 1993 | Seattle business licence | address · medium |
| Earthjusticevia EARTHJUSTICE | # 610 | Apr 1989 | Seattle business licence | address · medium |
| WASHINGTON DEFENDER ASSOCIATION | # 258 | Oct 1983 | Seattle business licence | address · medium |
Seattle / King County assessment roll
Parcel record
| Field | Value |
|---|---|
| parcel (major-minor) | 0942000550 |
| Site address | 810 3RD AVE |
| Land use (DOR) | — Office |
| Building area (actual) | 201,480 sq ft |
| Floors / units / buildings | 8 / — / 1 |
| Lot size | — |
| Year built | 1907 |
| Zoning (primary) | — |
| Land value | $31,968,000 |
| Building value | — |
| Total assessed value | $31,969,000 |
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
- 810 3RD AVE
- City
- Seattle
- ZIP
- 98104
Within ~650 m
Nearby office buildings
No other office parcels within ~650 m.
How does 810 3RD AVE compare with other Seattle office buildings?
At 201,480 sq ft, 810 3RD AVE is about 4 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.
Its assessed value works out to $159 per square foot of building area, against $230 across all office floor area on the roll.
The last recorded sale priced it at $335 per square foot.
Does the owner of 810 3RD AVE 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 810 3RD AVE recently?
1 recorded transfer is on file for this parcel, the latest dated Jul 2018.
What does “Office” mean for this parcel?
The Seattle / King County roll classifies parcel (major-minor) 0942000550 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 810 3RD AVE?
Seattle / King County's published roll does not include owner names, so no owner is shown.
What companies have offices at 810 3RD AVE?
10 active business locations at this building appear in Seattle / King County public records, including SYNECT LLC, SEXUAL VIOLENCE LAW CENTER, 7 ELEVEN 37068A, NORTHWEST PROPERTY TAX CONSULTANTS, CH2M HILL INC. Public records under-count tenants that don't hold a local receipt or register the address.
How big is 810 3RD AVE?
The Seattle / King County roll records 201,480 sq ft of building area, 8 floors, a build year of 1907.
What is the assessed value of 810 3RD AVE?
$31,969,000 on the Seattle / King County roll. Assessed values are taxable-roll figures, not market prices.
When did 810 3RD AVE last sell?
The last recorded transfer was in Jul 2018 for $67,500,000 ($335 per square foot).
What is the parcel (major-minor) for 810 3RD AVE?
Parcel (major-minor) 0942000550, site address 810 3RD AVE, 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 810 3RD AVE
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) 0942000550.
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, “810 3RD AVE, Seattle, WA (parcel (major-minor) 0942000550)”, https://buildingcensus.com/offices/seattle/office-building-307ad7cb (data as of September 20, 2026).