Local research · updated July 2026
Replacement Windows in Seattle, Washington
Seattle's window problem is written in water, not cold. The marine climate here is cool, wet, and mild — rarely brutal, but persistently damp — and that steady moisture, not deep freeze, is what rots sills and grows mold on old single-pane wood sashes. It meets a housing stock full of Craftsman bungalows and foursquares, roughly 90,000 of them built before 1940, many still running original or second-generation windows. Layer on one of the strictest state energy codes in the country and some of the highest install labor rates anywhere, and window replacement in Seattle is as much about managing condensation and wood rot as it is about the energy bill.
Short answer
In Seattle, a standard replacement window (double-hung, casement or slider) typically costs $620–$3,540 installed. Bay and bow windows run $3,110–$9,950+, and a sliding patio door $1,865–$6,215. Frame material and the glass package decide where a project lands in that range.
Planning ranges built from NREL and BLS cost data, localized to Seattle with the BEA Regional Price Parity for Seattle-Tacoma-Bellevue, WA (2024). How we estimate →
54.2%
of Seattle homes were built before 1980, the era of single-pane and early aluminum windows
Source: U.S. Census Bureau, 2019–2023 ACS 5-Year Estimates
1974
median year built across Seattle's 382,933 housing units
Source: U.S. Census Bureau, 2019–2023 ACS 5-Year Estimates
U ≤ 0.22
the ENERGY STAR v7.0 number that matters most in the Northern zone
Source: EPA ENERGY STAR v7.0
Window installers in Seattle
Compare companies serving Seattle. Request a free, no-obligation quote and we route it to the company or a vetted local installer.
| Company | Location | Request a quote |
|---|---|---|
 4.8 · 200,000+ reviews | Renton, WA | Get a quote → |
| 1Champion Replacement Windows of SeattleChampion | Kent, WA | Get matched → |
| 2Pella Windows and Doors Showroom of Bothell, WAPella | Bothell, WA | Get matched → |
| 3Pella Windows and Doors Showroom of Tacoma, WAPella | Tacoma, WA | Get matched → |
| 4Window NationWindow Nation | Auburn, WA | Get matched → |
| 5Window World North Puget SoundWindow World | Mountlake Terrace, WA | Get matched → |
Renewal by Andersen of Western Washington
4.8 · 200,000+ reviewsShowrooms in Renton, Lakewood & Marysville · serving the Seattle metro
Full-service manufacturer and installer, transferable warranty, local crews. Why it's our Top Pick
Get a quote →Listings compiled from manufacturer dealer locators and public business records. Premier and Sponsored Partners pay for placement and are labeled as such; star ratings shown are reported by the partner, with the source and date beside them. See our advertising disclosure. Contacting a company shares your details with it (or a vetted local installer) so it can reach you about your project.
Are you a window company? Claim your listing to take quote requests from Seattle homeowners directly.
What drives window decisions in Seattle
- Persistent damp, not cold, is the driver: original wood double-hungs collect interior condensation that feeds rot at the sill and mold in the frame.
- Classic single-pane Craftsman and foursquare windows dominate the pre-war stock — beautiful, leaky, and often past the point where paint and putty can save them.
- The Washington State Energy Code is among the most stringent in the nation and raises the performance bar that permitted replacements must clear.
- Seattle's high construction labor rates widen the spread between bids — the same window can carry very different install pricing across contractors.
Replacement windows & doors by type in Seattle
Local cost ranges and Northern-zone efficiency guidance for each window and door style, specific to Seattle homes:
Ranges localized to Seattle's cost level: national planning ranges shifted by the BEA Regional Price Parity for Seattle-Tacoma-Bellevue, WA (111.1, U.S. = 100; 2024). How we estimate local costs →
Efficiency requirements for Seattle's climate
Seattle sits in the ENERGY STAR Northern zone (IECC zone 4C (marine), King County). Under the v7.0 specification, qualifying windows need a U-factor of 0.22 or lower with a solar heat gain coefficient (SHGC) of at least 0.17. Heating-dominated climate: the window must hold heat in (very low U-factor) while still letting some free solar warmth through in winter (minimum SHGC). Equivalent-performance tradeoffs allow U-factors of 0.23–0.26 when paired with progressively higher solar gain.
Not sure what these numbers mean? Read our plain-English guide to U-factor and SHGC.
What replacement windows cost here
Two local forces push Seattle quotes above what national averages assume. Labor is the first: install rates here are among the highest in the country, and on old homes that adds up fast. Frame condition is the second — pre-1940 wood windows with rot, out-of-square openings, or lead paint often force full-frame replacement plus repair rather than a quick insert. On the product side, Washington's energy code effectively requires Northern-zone glass, so budget bids built around basic double-pane rarely reflect what will actually pass permit. The offset is durability: getting water and air management right on a century-old frame solves the condensation and rot problem that keeps recurring.
For a breakdown by frame material and install type, see our full cost guide.
Rebates & incentives in Washington
The federal window tax credit (25C) ended for projects placed in service after December 31, 2025. If your windows were installed in 2025, you can still claim it on your 2025 return — but for new projects there is no federal window credit. State and utility programs are now the main source of window incentives.
Washington runs IRA Home Energy Rebate programs; whole-home efficiency retrofits can include windows. Confirm current status and funding availability before promising rebate money.
- Seattle City Light / Puget Sound Energy efficiency programs. Washington's utilities — including Seattle City Light and Puget Sound Energy (PSE) — fund home efficiency and weatherization; window replacement generally qualifies as part of whole-home efficiency work. (Seattle City Light, Puget Sound Energy program pages)
Washington enforces the Washington State Energy Code, among the strictest in the nation; Seattle permits through the Department of Construction & Inspections (SDCI), and the code sets a high bar for replacement windows.
Replacement windows in nearby metros
Not in Seattle proper? These nearby markets carry the same local research: housing-age data, climate-zone specs, and current rebate status for each city:
Seattle window replacement FAQ
›Do I need a permit to replace windows in Seattle?
It depends on the scope. The Seattle Department of Construction & Inspections (SDCI) generally treats like-for-like replacement in an existing opening as minor work, but a permit is required once you change the building envelope — enlarging or moving an opening, altering a load-bearing header, or reducing egress, light, or ventilation — and for work above SDCI's minor-repair cost threshold. Because rules change and older homes have quirks, confirm with SDCI (seattle.gov/sdci) before you sign, and make sure your contractor pulls any permit in their name.
›My old wood windows have condensation and some rot — repair or replace?
In the damp Puget Sound climate this is the central question. Sound frames that are square and only surface-weathered can often be restored, and paired with storm windows they preserve a Craftsman home's character — a legitimate path, especially in historic areas. But be honest about the moisture: if the sill or lower rails are actively rotting, or condensation keeps returning between the panes, restoration is treating a symptom. Full-frame replacement lets the installer correct the flashing and air sealing that let water in, which is usually the real fix.
›What efficiency numbers should Seattle windows hit?
Seattle sits in the ENERGY STAR Northern zone (IECC climate zone 4C, marine). The current Northern v7.0 spec targets a U-factor of 0.22 or lower, with an equivalent path around 0.23–0.26 for products that pair a slightly higher U-factor with higher solar heat gain — useful in a cloudy climate where free winter sun is welcome. Prioritize the U-factor rating on the NFRC label; in a heating-dominated marine climate it matters more than solar control, and it is also what the state energy code checks.
›Are there tax credits or rebates for window replacement in Washington?
The federal 25C energy-efficient home improvement credit expired December 31, 2025, so that route is closed for new projects. In Washington, incentives now come mainly from utilities and state programs rather than a federal window credit. Seattle City Light and Puget Sound Energy (PSE) — the two main electric utilities in the metro — run weatherization and efficiency programs, and eligibility and amounts depend on which utility serves your address and current program rules. Check your specific utility's residential energy pages, and start with a home energy assessment, which documents the baseline these programs pay against.
Sources
- — U.S. Census Bureau, American Community Survey 5-Year Estimates (B25034, B25035)
- — EPA ENERGY STAR Version 7.0 Residential Windows specification
- — DOE/PNNL IECC climate zone assignments by county
- — IRS, 25C Energy Efficient Home Improvement Credit (P.L. 119-21)