Commercial buildings in King County
BrokerHQ, a Seattle tenant-representation intelligence platform, tracks 23,742 commercial buildings in King County as of August 7, 2026, sourced from King County Assessor parcel records with residential uses excluded.
Updated August 7, 2026See how this is built
King County, as of August 7, 2026
Move signals are permit-derived
Seattle's benchmarking law threshold
How many commercial buildings does BrokerHQ track in King County?
BrokerHQ tracks 23,742 commercial buildings in King County as of August 7, 2026, built from King County Assessor parcel records. Records are re-ingested as the Assessor publishes updated parcel data, so the count reflects the county's own file rather than a listings database.
What counts as commercial here?
Commercial means office, industrial and retail property. Parcels carrying residential present-use codes are excluded, so single family homes, condominiums and apartment parcels never enter the count. That exclusion is why this number is smaller than a raw parcel count for the same county.
Where do building move signals come from?
Move and build-out signals are permit-derived and tracked back to 2005, read from Seattle Department of Construction and Inspections records covering building, land use, electrical and occupancy permits, with the Washington SEPA register adding environmental review for larger projects. A tenant improvement permit pulled on a floor is a move that has already been decided and not yet announced.
How often does building data refresh?
County property records are re-ingested weekly where the registry supports it and monthly otherwise, and composite signals are recomputed nightly. Filings from public companies that touch property, such as a disclosed lease commitment, land within 24 hours of release.
What does the energy benchmarking data add?
Seattle's Energy Benchmarking Law requires owners of non-residential and multifamily buildings larger than 20,000 square feet to track energy performance and report it annually. That gives a recurring, owner-filed record on exactly the buildings a tenant rep broker cares about, independent of anything the listing market publishes.
Does this include listings or asking rents?
No. This is parcel, permit and sales-record data from the public file, not a listings feed. BrokerHQ does not infer lease terms from comparable buildings; when there is no actual record, no lease is claimed. Ownership and sales figures come from county-verified transactions.
Which public records does this come from?
Every record below is published by the body that created it, and every link goes to that body rather than to a reseller. You can check any number on this page against them yourself.
- King County Assessor
Parcel records and verified sales transactions. The primary source for the building count on this page.
- Seattle Department of Construction and Inspections
Building, land use, electrical and occupancy permits, the basis for move and build-out signals back to 2005.
- Washington SEPA register
Environmental review documents for larger projects, posted by the Department of Ecology since 2000.
- City of Seattle energy benchmarking
Annual owner-reported energy performance for non-residential and multifamily buildings over 20,000 square feet.
How is the count actually built?
The primary source is the King County Assessor. Commercial here includes office, industrial, and retail property. Parcels carrying residential present-use codes are excluded, so single family homes, condominiums, and apartment parcels do not enter the count. Records are re-ingested as the Assessor publishes updated parcel data. Permit records from Seattle Department of Construction and Inspections are matched to those parcels, with the match basis recorded, and a second independent source is required before a signal surfaces.
Where to look next
- The full data map how a permit becomes a signal, then a verified lead.
- Public companies in the Puget Sound region the occupier side of the same graph.
- Methodology coverage, cadence, and what is deliberately excluded.
Last updated August 7, 2026