How much does it cost to replace windows in Seattle?

$10,855 was the median declared permit value for data years 2023-2026 in Seattle, WA. Single-family and duplex window replacement permits issued in Seattle declared a typical range (middle half of 202 City of Seattle permit data points, Seattle, WA, 2023-2026) of $7,866 to $16,034.

Updated 2026-10-28

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Seattle, WA: declared value on building permits
What was measured	Median declared value	Declared value range (middle half)
Single-family and duplex window replacement permits issued in Seattle declared	a median declared value on building permits of $10,855	the typical range (middle half of 202 City of Seattle permit data points, Seattle, WA, 2023-2026) was $7,866 to $16,034

Declared permit values are what applicants reported to the city; final contract prices can differ.

How measured: residential single-job permits; declared values below the low-value floor for the same job removed (0 rows). Source: City of Seattle, SDCI 'Building Permits' (76t5-zqzr), data read 22 October 2026.

These figures are estimates from City of Seattle, SDCI 'Building Permits' (76t5-zqzr), data years 2023-2026, read 22 October 2026, for Seattle, WA. They are not a quote, and they are not a promise of what any contractor on InstaBids will charge. Your price depends on your home, the materials and the contractor. Get written bids before you decide.

How we know: By InstaBids editorial team with AI research agents. Sources read: 16 October 2026

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What the job includes, the line items to ask for and how to compare bids: the national window replacement cost guide.

What do Seattle window permits declare?

Each Seattle figure above is a declared permit value: what the applicant told the permit office the window job was worth when applying. It is not an invoice.

The count covers single-family and duplex building permits whose description names a window replacement. Permits for a new home, revision and renewal permits, demolition-only permits and permits that also name another job were left out first.

All 202 matched permits carried a declared value. None fell below the low-value floor for this job, so all 202 permits are behind the figures.

How does Seattle compare with the national survey?

For the national picture, the Census Bureau's American Housing Survey asked households about the work done on their home and whether they hired it out. It has no line for windows alone: its item reads "Added or replaced doors or windows", so a new entry door and a full set of new windows share one range.

Source: U.S. Census Bureau, AHS 2023 Value Labels Package, read 16 October 2026.

United States: homeowner survey
What was measured	Median	Typical range (middle half)
Households in the American Housing Survey that hired someone to add or replace doors or windows reported	a median of $4,000	the typical range (middle half of 1,477 American Housing Survey data points, the United States, 2021-2023) was $1,300 to $10,000
When the household fitted them itself	a median (572 American Housing Survey data points, the United States, 2021-2023) of $750	—

How measured: hired-out finished jobs, survey-weighted, not adjusted for inflation; do-it-yourself jobs the same way. Source: U.S. Census Bureau, American Housing Survey 2023, data read 16 October 2026.

These figures are estimates from U.S. Census Bureau, American Housing Survey 2023, data years 2021-2023, read 16 October 2026, for the United States. They are not a quote, and they are not a promise of what any contractor on InstaBids will charge. Your price depends on your home, the materials and the contractor. Get written bids before you decide.

Full national guide: How much does it cost to replace windows?

The Seattle median declared value sits above the national survey median for hired-out door and window jobs.

The two are different kinds of record: a survey answer is what a household remembers paying, while a permit value is what an applicant wrote down before the work began. This page keeps them apart and never blends them into one number.

Which window rules does Seattle publish?

Example rule, Seattle Department of Construction and Inspections window guidance: “Egress windows: a. New: Required for 1 window/new sleeping room and 1 window/new basement. i. Min. net clear area = 5.7 SF* (min. 3’0” x 4’6” if double hung or 4’0” x 3’6” if slider). *5.0 SF for openings at grade ﬂoor or below. ii. Min. net clear opening width = 20”; min. net clear opening height = 24”. iii. Max. sill height = 44” iv. When sill is below grade, provide min. 3’x3’ window well. If deeper than 44”, provide a permanent ladder or steps. b. Replacement egress windows in existing permitted sleeping rooms and basements ONLY. i. Must be the manufacturer largest standard size that ﬁts in the existing opening ii. Net openings cannot be reduced and must be greater than or equal to existing net openings”

Source: Seattle Department of Construction and Inspections, read 9 November 2026.

Example rule, Seattle Department of Construction and Inspections window guidance: “The term “commercial buildings” includes all buildings except single-family, duplex, and townhouse construction.”

Source: Seattle Department of Construction and Inspections, read 9 November 2026.

Example rule, Seattle Department of Construction and Inspections window guidance: “Heat flow through fenestration is evaluated using a “U-factor,” for which lower numbers indicate better performance.”

Source: Seattle Department of Construction and Inspections, read 9 November 2026.

Example rule, Seattle Department of Construction and Inspections window guidance: “These U-factors consider the entire glass plus frame assembly, so are not just the center-of-glass values.”

Source: Seattle Department of Construction and Inspections, read 9 November 2026.

Example rule, Seattle Department of Construction and Inspections window guidance: “Where some or all of an existing fenestration unit is replaced with a new fenestration product, including sash and glazing, the replacement fenestration unit shall meet the applicable requirements for U-factor and SHGC in Table R402.1.3. Where more than one replacement fenestration unit is being installed, an areaweighted average of the U-factor and SHGC of all replacement fenestration shall be permitted to be used to demonstrate compliance.”

Source: Seattle Department of Construction and Inspections, read 9 November 2026.

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Sources for the figures on this page

City of Seattle, SDCI 'Building Permits' (76t5-zqzr), https://data.seattle.gov/Built-Environment/Building-Permits/76t5-zqzr, read 22 October 2026. InstaBids computed medians and middle-half ranges.
U.S. Census Bureau, American Housing Survey 2023, https://www.census.gov/programs-surveys/ahs/data/2023/ahs-2023-public-use-file--puf-.html, read 16 October 2026. U.S. government work; no endorsement implied.
U.S. Census Bureau, AHS 2023 Value Labels Package, www2.census.gov/programs-surveys/ahs/2023/AHS 2023 Value Labels Package.zip, read 16 October 2026.
Seattle Department of Construction and Inspections, www.seattle.gov/documents/Departments/SDCI/Forms/BuildingEnergyCodeSTFICklist.pdf, read 9 November 2026.
Seattle Department of Construction and Inspections, www.seattle.gov/DPD/Publications/CAM/Tip428.pdf, read 9 November 2026.
Seattle Department of Construction and Inspections, www.seattle.gov/documents/Departments/SDCI/Codes/SeattleEnergyCode/2021SECResChapter5.pdf, read 9 November 2026.