18400 NE Union Hill Rd, Redmond, WA 98052

Office · Redmond · Seattle-Bellevue metro, WA

One of 123 reachable office buildings in Redmond. Larger than 94% of office buildings in Redmond (median 7,931 SF), derived from assessor records.

Usable building area
269,952 SF, King County Assessor
County gross area
274,848 SF, King County Assessor
Excluded area
4,896 SF outside primary usable area
Lot size
654,048 SF, King County Assessor
Year built
2000, King County Assessor
Stories
3, King County Assessor
Buildings on parcel
3, King County Assessor
Predominant use
Office Building, King County Assessor
Assessed value
$101,458,700, per the King County Assessor (not a market appraisal)
Assessed value per usable SF
$375.84/SF, derived from assessor records
Usable area / lot
0.41, derived from assessor records
Vintage
2000s vintage
Zoning
BP, King County
County use code
Office Building

Nearby comparable buildings

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

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Sale history and market context

MakeMe Estimate: $129M (estimated market value), with a likely range of $114M to $148M (half of recent verified sales in this segment landed inside that range). Based on 6 verified arm's-length comparable sales (through 2026-06-01). Not an appraisal. How this estimate works.

lower confidence: 1 comparable sale within 3 miles; nearest 1.1 mi. This property type carries wider measured error; treat the estimate as a starting point.

Comparable sales used as evidence

Recorded arm's-length sales of similar buildings nearby; nearer and more recent sales rank first. Buyer and seller names are withheld. Get this data via API.

Market context: Office in Redmond

median verified sale $632.11/SF over the trailing 24 months; 5 sales in the last 12 months and 9 in 24 (newest verified sale 2026-02); the middle 80% of recent sales traded at 1.02x to 3.10x their county assessed value, median 1.30x (9 sales with usable county values).

This estimate sits at 1.27x county assessed value, the 33rd percentile of those recent sale premiums.

Computed from 139 verified arm's-length sales in King County public records (9 in the trailing 24 months). Free public records. Not an appraisal.

Last sold: 1998-10-01 for $4,504,575 (recorded arm's-length sale).

Current ownership dates to 2020 (about 6 years) per recorded transfers.

Source: King County recorded sales extract; buyer and seller shown only when a company or organization. Individual names are withheld.

Value over time

$0$50M$100M$150M$200M201120142017202020232026$129M$101MCounty assessed valueMakeMe Estimate range

Dark line: county assessed value per King County tax rolls. Blue line: our estimate; dashed years are a modeled backcast built from recorded arm's-length sales in the building's segment, not estimates published at the time, and years without enough sales stay unmodeled. The shaded range is the model's measured error band; about half of verified sales in the segment land inside it. Diamonds: recorded arm's-length sales. Not an appraisal. How this estimate works.

Land, site, and value history

Assessed value moved from $52,979,100 (2011) to $101,458,700 (2026), up 92% over 15 years, per county tax rolls. The 2026 roll splits $101,458,700 into $22,891,600 land and $78,567,100 improvements.

Taxes

Permit history

Source: King County permit records (newest first).