InstaBidsHow much does it cost to replace windows in Marin County?
$10,000 was the median declared permit value for data years 2023-2026 in Marin County, CA. Residential window replacement permits issued in Marin County declared a typical range (middle half of 289 Marin County, CA permit data points, Marin County, CA, 2023-2026) of $4,956 to $18,800.
Updated 2026-10-28
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| What was measured | Median declared value | Declared value range (middle half) |
|---|---|---|
| Residential window replacement permits issued in Marin County declared | a median declared value on building permits of $10,000 | the typical range (middle half of 289 Marin County, CA permit data points, Marin County, CA, 2023-2026) was $4,956 to $18,800 |
Declared permit values are what applicants reported to the county; final contract prices can differ.
How measured: residential single-job permits; declared values below the low-value floor for the same job removed (1 row). Source: County of Marin, CA, 'Building Permit' (mkbn-caye), data read 22 October 2026.
These figures are estimates from County of Marin, CA, 'Building Permit' (mkbn-caye), data years 2023-2026, read 22 October 2026, for Marin County, CA. 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.
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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 Marin County window permits declare?
Each Marin County 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 residential building permits in Marin County whose description names a window replacement. One permit for a new home or for work not on an existing home, one demolition-only permit and five permits that also name another job were left out first; no revision, renewal or as-built permit matched.
All 290 matched permits carried a declared value. One value fell below the low-value floor for this job and was removed, which leaves the 289 permits behind the figures.
How does Marin County 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.
| 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 Marin County 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.
Who must use lead-safe practices when replacing windows?
ENERGY STAR's window page says that "any contractor or landlord replacing a window must use lead-safe work practices to prevent lead dust hazards", in a warning about houses built before 1978.
Source: ENERGY STAR (U.S. EPA), Residential Windows, Doors and Skylights, read 16 October 2026.
What window guidance applies in Marin County?
Example rule, Marin County Environmental Health Services window work at residences served by septic systems: “Projects that constitute typical maintenance and repair activities such as re-roofing, installing new windows, making energy efficiency improvements, plumbing permits, electrical permits, new siding, etc., do not require any permit or review by EHS.”
Source: Marin County Environmental Health Services, read 9 November 2026.
Example rule, Marin County Community Development Agency window guidance: “Residential maintenance and minor improvements? You don't need to submit plans to get a permit. Apply online and get your permit as quickly as you can complete the application.”
Source: Marin County Community Development Agency, read 9 November 2026.
Example rule, Marin County Community Development Agency window guidance: “These online permits are for jobs that replace something that exists now. You do not need to have plans to describe your work. We will not ask for plans.”
Source: Marin County Community Development Agency, read 9 November 2026.
Example rule, Marin County Community Development Agency window guidance: “Building – siding, stucco, re-roof, same size/location window/door replacement”
Source: Marin County Community Development Agency, read 9 November 2026.
Example rule, California Energy Commission statewide residential replacement-window provisions: “Removing glazing from an existing wall and reinserting up to the same area of glazing in a different opening is an alteration, covered by Section 150.2(b)1B.”
Source: California Energy Commission, read 9 November 2026.
Example rule, California Energy Commission statewide residential replacement-window provisions: “B. Replacement fenestration. New manufactured fenestration products installed to replace existing fenestration products of the same total area shall meet the U-factor and Solar Heat Gain Coefficient requirements of Sections 150.1(c)3A, and 150.1(c)4.”
Source: California Energy Commission, read 9 November 2026.
Example rule, California Energy Commission statewide residential replacement-window provisions: “Exception 1 to Section 150.2(b)1B: Replacement of vertical fenestration no greater than 75 square feet with a U-factor no greater than 0.40 in Climate Zones 1-16, and a SHGC value no greater than 0.35 in Climate Zones 2, 4, and 6 through 15.”
Source: California Energy Commission, read 9 November 2026.
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Sources for the figures on this page
- County of Marin, CA, 'Building Permit' (mkbn-caye), https://data.marincounty.gov/d/mkbn-caye, read 22 October 2026. InstaBids computed medians and middle-half ranges.
- Contains information from Building Permit (County of Marin, CA), which is made available here under the Open Database License (ODbL). Method.
- 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.
- ENERGY STAR (U.S. EPA), Residential Windows, Doors and Skylights, www.energystar.gov/products/res_windows_doors_skylights, read 16 October 2026.
- Marin County Environmental Health Services, assets.marincounty.gov/marincounty-prod/public/2024-03/septic-system-residential-improvement-policy_.pdf, read 9 November 2026.
- Marin County Community Development Agency, www.marincounty.gov/departments/cda/building-and-safety/how-apply-building-permit, read 9 November 2026.
- California Energy Commission, www.energy.ca.gov/filebrowser/download/8641, read 9 November 2026.
- California Energy Commission, www.energy.ca.gov/sites/default/files/2025-07/CEC-400-2025-010-F_0.pdf, read 9 November 2026.