How Much Does Window Replacement Cost in Seattle? 2026 Price Ranges and What Drives Them

Name: Harley Exteriors
Price range: $$
Rating: 5

Window replacement cost in Seattle runs about $350 to $2,750 per window in Angi's 2026 data, and a whole-house project averages $14,453 before 10.55% sales tax. Seattle's energy code also requires replacement windows to rate U-0.30 or better, which rules out the single-pane glass at the low end of online price lists.

Updated October 29, 2026

Ask around Puget Sound what a new window costs and you’ll hear numbers a few hundred dollars apart, or a few thousand. Angi puts the window replacement cost Seattle homeowners pay at $350 to $2,750 per window. [1] homeyou’s 2026 range is $383 to $525. [2] They aren’t pricing the same job.

Five things open that gap: frame material, window style, glass package, install method and permits. A Seattle code rule also cuts off the bottom of the range before anyone writes a quote, and it’s covered right after the price table. If you’re comparing bids for replacement windows in Seattle, start with the numbers below.

Direct Answer

Window replacement cost in Seattle runs about $350 to $2,750 per window in Angi’s 2026 data, and a whole-house project averages $14,453 before 10.55% sales tax. Seattle’s energy code also requires replacement windows to rate U-0.30 or better, which rules out the single-pane glass at the low end of online price lists.

TL;DR

Most Seattle window replacement runs $350 to $2,750 per window, and a whole-house project averages $14,453.
Replacement windows in Seattle must meet a U-factor of 0.30 or lower, so single-pane price lines don’t apply.
Style and glass both move the price. A picture window starts lowest and a bay or bow highest.
An insert keeps the old frame, while full-frame removes it. The frame’s condition usually decides.
Sales tax of 10.55% applies to the whole Seattle job, labor included. Permits depend on value and envelope changes.
The federal window credit ended with 2025. PSE pays $50 to $200 per window when PSE heats your home.
Check every bid for the NFRC U-factor, the install method, the permit and tax on its own line.

One liner: In Seattle, the energy code sets the price floor, and style, glass and install method decide where your quote lands above it.

Key Numbers

Stat	What it measures	Source
$350 to $2,750	Seattle cost per window	Angi, August 2026
$14,453 (normal range $5,735 to $23,555)	Seattle whole-house average	Angi, August 2026
0.30	Replacement window U-factor cap	Washington State Energy Code, Residential, R503.1.1.1; 2021 Seattle Energy Code, Effective March 15, 2024
1.10	Default U-factor, single-pane metal with thermal break	2021 Seattle Energy Code, Table R303.1.3(1), 2021 edition
May 3, 2027	Next residential energy code effective date	WSU Energy Program, 2026
0.27 (proposed)	Proposed U-factor in the 2024 code	State Building Code Council, June 2026
$6,000 in any six months	Permit exemption value limit	2021 Seattle Residential Code R105.2, 2021 edition
10.55%	Seattle sales tax	Washington Department of Revenue, October to December 2026
Ended for improvements after December 31, 2025	Federal energy credit for windows	IRS, April 2026
$50 or $100 per window, up to $750 or $1,500	PSE standard window rebate	Puget Sound Energy, October 2026
$200 per window, up to $2,000	PSE Efficiency Boost rebate	Puget Sound Energy, October 2026

How Much Does Window Replacement Cost in Seattle?

In short: Most Seattle window replacement costs $350 to $2,750 per window, with whole-house projects averaging $14,453. [1]

Most Seattle window replacement runs $350 to $2,750 per window, according to Angi’s 2026 data. The average whole-house project comes to $14,453, and the normal range is $5,735 to $23,555. [1] Frame material, window style, glass package and install method decide where your quote lands in that spread.

Here’s how per-window prices turn into a project total. Angi puts the median Seattle home at 1,890 square feet with 15 to 20 windows. [1] At its $750 per window example rate, 15 windows come to $11,250 and 20 windows come to $15,000.

Ordering several windows at once can lower the price of each, since installers may charge less per window when many go in together. [2]

Window replacement cost per window by frame material, Seattle

Frame material	Per-window figure (Angi, 2026)
Vinyl	$100 to $900
Wood	$150 to $1,300
Fiberglass	$500 to $1,500
Aluminum	$75 to $400

Angi doesn’t say whether these material lines include labor, so its installed range of $350 to $2,750 per window is the better yardstick for a full quote. [1] Aluminum and vinyl start lowest, and fiberglass starts highest.

One catch before you budget from the bottom of any of these ranges. Some of the cheapest window products in online price tables can’t legally go into a Seattle home as replacements.

Why the Cheapest Prices Online Don’t Apply in Seattle

In short: Seattle replacement windows must rate U-0.30 or lower, so single-pane glass is off the table. [3][4][5]

In Seattle, a replacement window has to meet the state energy code, and that code caps a window’s U-factor at 0.30. [3][4][5] Single-pane glass can’t get close, so a single-pane price line doesn’t describe a job that passes code here.

U-factor measures how fast a window lets heat escape. Lower is better. Here’s how single-pane glass compares with the cap.

Seattle’s replacement window cap vs single-pane glass

Window	U-factor	Meets the 0.30 cap?
Seattle cap for a replacement window	0.30	This is the limit
Single-pane, metal frame with thermal break (code default)	1.10	No
Worst single-pane units (city labeling guide)	1.30	No

Both single-pane figures are more than three times the cap. [6][7]

The rule comes from two codes. Seattle’s residential code says replacement windows must comply with the Washington State Residential Energy Code. [3] The state code says a replacement unit, sash and glass included, must meet the table U-factor. When several windows go in at once, an area-weighted average of all of them can show the job passes. [4]

So when Angi lists single-pane glass at $200 to $500 per window as the most affordable option, that line doesn’t fit a Seattle replacement. [1] The real starting point is a double-pane unit rated at U-0.30 or lower.

The code applies even when a job needs no permit. [8] To check a quote, ask for the U-factor printed on each window’s NFRC label. The average across the job has to land at 0.30 or below.

That number is set to drop. Washington’s next energy code takes effect May 3, 2027, and the State Building Code Council’s residential update proposes a U-factor of 0.27. [9][10]

Window Replacement Cost per Window by Style

In short: Picture windows start lowest and bay or bow windows highest in both price tables. [1][11]

Style moves the price because it changes the build. A picture window is fixed glass with no moving parts. A bay window joins three angled panels, a bow uses four or more, and both project out from the wall. That puts them at opposite ends of the table.

Window replacement cost per window by style

Style	Seattle (Angi, 2026)	National (Fixr, 2026)
Single-hung	$100 to $400	$250 to $700
Double-hung	$150 to $650	$300 to $1,000
Casement	$150 to $1,000	$400 to $1,200
Sliding	Not published	$700 to $1,500
Picture	$65 to $700	$300 to $1,600
Awning	Not published	$300 to $800
Bay	$900 to $7,100	$900 to $4,500
Bow	Not published	$1,500 to $8,000
Arched or custom shape	$350 to $1,000 arched, $1,000 and up custom	Not published

Neither source says for certain that its style figures include installation, so use the table to compare styles, not as a quote. [1][11] Angi’s Seattle data skips sliding, awning and bow windows, which is why the national column is there. If a projecting window is on your list, Harley Exteriors installs bay and bow windows in both layouts.

How the Glass Package Changes the Price

In short: Glass sets the U-factor, so the NFRC label matters more than the pane count. [1][13]

Glass is where Seattle’s energy rule shows up on the bill. Pane count, coatings and gas fill all change how well a window insulates, and the rated U-factor decides whether it can go in at all. [13]

Window glass cost per window and the Seattle code note

Glass	Per-window figure (Angi)	Seattle code note
Single-pane	$200 to $500	Can’t meet the U-0.30 cap as a replacement
Double-pane	$500 to $2,000	Passes when the NFRC label shows 0.30 or lower
Low-E	$300 to $1,100	Check the label
Triple-pane	$1,000 to $4,000	Check the label
Tempered	$200 to $700 (national)	Required in hazardous locations

The double-pane range alone spans $1,500, so the label tells you more than the pane count does. [1][4][6] Tempered glass is a code item, too. Seattle’s residential code says replacement glass in hazardous locations must meet the safety glazing rules in Section R308. [3][12]

On the savings side, ENERGY STAR estimates that replacing poor-performing windows with certified ones cuts energy costs by about 12% a year, a national average that varies by climate. [20]

Harley Exteriors’ replacement windows include many configurations that meet ENERGY STAR performance standards, and the consultant confirms which options fit your home before you order.

Full Frame vs Insert Window Replacement Costs

In short: An insert keeps the old frame and a full-frame job removes it. Frame condition usually picks the method. [14]

The two install methods differ in how much of the old window comes out. With an insert, the old sash, side jambs and trim come out, the original frame stays, and the new window fits inside it. With a full-frame job, the whole frame comes out and the new window goes into the rough opening. [14]

Insert vs full-frame window replacement

Factor	Insert	Full-frame
What comes out	Sash, side jambs, trim	The whole frame
When it fits	Frame and sill are sound and square	Frame is damaged, a bigger opening is wanted, or the frame won’t take an insert
Glass area	May end up smaller than before	Can match the old window or grow
Per-window figure (Angi, national)	$100 to $300 retrofit	$180 to $1,500

Angi files those under installation type and doesn’t say whether the window itself is included, so read the insert window replacement cost and full frame window replacement cost lines as a comparison, not a total. [12] The frame’s condition usually picks the method before price does.

When the old frame is rotted, repair joins the bill. Angi’s Seattle data puts dry rot repair at $170 to $890 and frame replacement at $225 to $1,120 per window. [19]

Two Seattle rules come into play. Changing the building envelope or reducing egress needs a permit no matter how small the job. [8] And a bedroom replacement window is exempt from the egress opening rules when it’s the manufacturer’s largest standard size that fits the existing frame or rough opening, in the same operating style or one with an equal or larger opening. [3] That exemption covers both methods.

Labor, Permits and Sales Tax in Seattle

In short: Labor, permits and 10.55% sales tax sit outside the window price in Seattle. [8][15][16]

Labor

Angi’s national labor range is $100 to $300 per window. [12] Windows above the first floor can cost more to install because they’re harder to reach. [2]

Permits

Online guides disagree here. One says like-for-like replacement in existing openings needs no Seattle permit, and another says most jobs do. The code ties it to value and to the building envelope. Seattle exempts minor repairs or alterations worth $6,000 or less in any six months, and in-kind replacement with no change to the envelope. A change to the envelope or a cut in egress always needs a permit. Either way, the work has to meet code. [8] Ask your installer whether your job needs a permit and who pulls it.

Sales tax

Washington taxes the gross contract price, and that includes labor, materials, permits and fees. The rate follows the job site, and the tax has to appear on its own line. [15] At Seattle’s rate, Angi’s $14,453 average project carries $1,525 in sales tax.

Sales tax by job site, October to December 2026

Job site	Combined rate
Seattle	10.55%
Bothell, Snohomish County part	10.50%
Tacoma	10.50%
Kent	10.40%
Bothell, King County part	10.30%
Everett	9.90%

Rates are from the Department of Revenue. [16]

Rebates, Tax Credits and Window Replacement Financing

In short: No federal credit remains for 2026 installs. PSE pays $50 to $200 per window when PSE heats your home. [13][17]

Start with what’s gone. The IRS says the federal energy credit covers improvements made through December 31, 2025, so a 2026 window install gets none. [17]

PSE window rebates

Puget Sound Energy still pays a rebate when PSE electricity or natural gas is your home’s main heat source. It covers existing site-built single-family homes, the windows have to be bought and installed by December 31, 2026, and you apply within 60 days. [13]

PSE window rebate by old window and new U-factor

Old window	New window U-factor	Standard rebate	Efficiency Boost (income-qualified)
Single-pane, wood or metal frame	0.23 to 0.30	$50 per window, up to $750	$200 per window, up to $2,000
Single-pane, wood or metal frame	0.22 or lower	$100 per window, up to $1,500	$200 per window, up to $2,000
Double-pane, wood or metal frame	0.23 to 0.30	None	None
Double-pane, wood or metal frame	0.22 or lower	$100 per window, up to $1,500	$200 per window, up to $2,000

The $200 per window figure you’ll see quoted online is the Efficiency Boost rate for income-qualified households, not the standard rebate. [1][13] On the standard rebate, replacing single-pane with a window rated U-0.22 or lower doubles the amount. Check which utility supplies your heating fuel before you count on it.

Window replacement financing

Harley Exteriors offers financing through an online application linked from its site, so the cost can be spread out instead of paid at once. Check the current promotions before you sign, and finance the full price with sales tax included.

What to Check on a Seattle Window Quote

In short: A comparable bid lists the U-factor, install method, permit, tax and warranty on separate lines. [18]

Washington’s Department of Labor and Industries tells homeowners to get at least three written bids and compare them carefully. [18] For a fair comparison, each bid should show these nine lines:

Window count, style and size for each opening
Frame material and product line
The NFRC U-factor for each window, with the job average at 0.30 or lower [4]
The glass package, including tempered glass where the code calls for it [3]
Insert or full-frame, and why [14]
Whether a permit is needed, and who pulls it [8]
Sales tax on its own line [15]
Whether the windows fit a PSE rebate tier [13]
Warranty terms, in writing

A bid that skips line 3 can’t be checked against Seattle’s rule. Then look up each contractor in the department’s verification tool and confirm an active license. [18] Before you sign, run through these questions to ask your contractor. Harley Exteriors holds Washington license #CC HARLEEI980JP.

Frequently Asked Questions

In short: Six quick answers on price, the code rule, permits, rebates and install method.

How much does window replacement cost in Seattle?

In Angi’s 2026 Seattle data, most window replacement runs $350 to $2,750 per window. A whole-house project averages $14,453, with a normal range of $5,735 to $23,555. [1] Sales tax and any permit come on top.

What is the average window replacement cost per window?

Angi’s example rate for Seattle is $750 per window, which puts 15 windows at $11,250 and 20 at $15,000. [1] Frame material, style, glass and install method move a window above or below that rate.

Can single-pane windows be installed as replacements in Seattle?

No. Replacement windows must meet the state energy code, which caps the U-factor at 0.30. [3][4][5] Single-pane glass rates far higher, so a code-compliant replacement starts with double-pane glass that carries an NFRC label at 0.30 or lower.

Do I need a permit to replace windows in Seattle?

It depends on the job. Seattle exempts minor work worth $6,000 or less in six months and in-kind replacement with no change to the building envelope. Changing the envelope or cutting egress needs a permit. The code applies either way. [8]

Is there a tax credit or rebate for new windows in 2026?

The federal credit ended with improvements made through December 31, 2025. [17] Puget Sound Energy pays $50 or $100 per window when PSE electricity or gas heats your home, or $200 for income-qualified homes, on windows installed by December 31, 2026. [13]

Does full-frame replacement cost more than an insert?

Its range runs higher. Angi’s national figures are $100 to $300 per window for a retrofit insert and $180 to $1,500 for full-frame. [12] Full-frame removes the whole old frame, so it fits damaged frames or larger openings. [14]

Get a Free Estimate for Your Windows

In short: A free estimate from Harley Exteriors turns these ranges into a written price for your home.

Harley Exteriors replaces windows across Puget Sound, from Seattle and Tacoma to Bothell and Snohomish, King and Pierce counties. A free estimate covers clear pricing, style recommendations and timeline details. Warranty options include a double lifetime warranty and transferable protection, based on product and install details. Call 425-999-4522 to book yours.

Definition Bank

Term	Meaning
U-factor	How fast a window lets heat escape. Lower is better.
NFRC label	The National Fenestration Rating Council sticker that shows a window’s rated U-factor.
Area-weighted average	The U-factor of all replacement windows averaged by their size, allowed to show a job meets code.
Double-pane	Two layers of glass sealed with a gap between them.
Low-E	A thin coating on glass that cuts heat transfer.
Tempered glass	Safety glass that breaks into small pieces. Required in hazardous locations.
Insert replacement	A new window set inside the old frame after the sash, side jambs and trim come out.
Full-frame replacement	A new window set into the rough opening after the whole old frame comes out.
Rough opening	The framed hole in the wall that holds the window.
Egress window	A bedroom window large enough to serve as an emergency exit.
Building envelope	The walls, roof, windows and doors that separate inside from outside.
In-kind replacement	Replacing a part with the same or similar part without changing the structure.
Gross contract price	The full amount charged for a job. Washington sales tax applies to all of it.
Efficiency Boost	Puget Sound Energy’s higher rebate tier for income-qualified customers.

Quick Facts

Seattle replacement window energy rule

Property	Value
Rule	Replacement windows must meet the Washington State Residential Energy Code
Code sections	Seattle Residential Code R4402.5.1; WSEC-R R503.1.1.1
U-factor cap	0.30
Several windows	Area-weighted average permitted
Next code	Effective May 3, 2027, proposed U-factor 0.27

Seattle permit exemption for minor work

Property	Value
Value limit	$6,000 or less in any six months
In-kind replacement	Exempt with no change to the building envelope
Always needs a permit	Changes to the building envelope or reduced egress
Code compliance	Required with or without a permit
Issued by	Seattle Department of Construction and Inspections

PSE window rebate

Property	Value
Who qualifies	PSE electricity or natural gas as primary heat, existing site-built single-family home
Standard	$50 per window up to $750 (U 0.23 to 0.30, single-pane only); $100 up to $1,500 (U 0.22 or lower)
Efficiency Boost	$200 per window up to $2,000, income-qualified
Deadline	Buy and install by December 31, 2026; apply within 60 days

Harley Exteriors

Property	Value
Office	22122 20th Ave SE, Suite 157, Bothell, WA 98021
Phone	425-999-4522
Washington license	CC HARLEEI980JP
Window styles	Single-hung, double-hung, casement, sliding, picture, awning, bay and bow, specialty
Warranty	Double lifetime warranty and transferable protection, based on product and install details
Financing	Online application linked from harleyexteriors.com