How Much Does Mold Removal Cost in Seattle?

What does a typical Seattle mold job cost?

According to Angi's Seattle cost guide, most local remediation jobs fall between $1,008 and $2,967, and the guide notes that Seattle runs roughly 17% below the national average for this kind of work. That average hides a wide spread. A bid for scrubbing one bathroom ceiling and a bid for opening up a wet exterior wall in a 1920s Craftsman are not the same job, even if both are called mold removal.

The same guide says most pros price the work at $10 to $25 per square foot, which works out to about $1,000 to $2,500 for a 100-square-foot area. Labor alone runs $75 to $120 per hour. Those two numbers explain most of the variation: how much material is affected, and how many crew hours it takes to contain, remove, clean and dry it.

Seattle price ranges by where the mold is

Location matters because access changes the labor. A crawl space job under an older Seattle house often means working on your back in a tight, low space, bagging out wet insulation and replacing a torn ground cover. Attic mold on roof sheathing usually traces back to bath fans venting into the attic or weak roof ventilation, and the cleaning itself is overhead work around nails and insulation. Daylight basements on hillsides in West Seattle or Beacon Hill can pick up seepage along the uphill wall, which is why basement mold cleanup has a broad range.

Walls show the widest spread of all, from $825 to $16,550. A small patch behind a vanity takes little time to reach; a slow window leak that has soaked framing along a whole elevation is not. If you suspect mold hiding inside a wall cavity, expect the bid to include opening the wall, and expect the price to change once the crew sees what is behind the drywall.

How do national figures compare?

National numbers are useful as a sanity check, but they are not Seattle prices. HomeGuide's 2026 national data puts typical remediation at $1,500 to $6,000, or $15 to $30 per square foot. Its national ranges by area run $500 to $2,000 for a bathroom, $1,500 to $4,000 for a crawl space, and $2,000 to $10,000 for an HVAC system or ducts, with whole-house work at $15,000 to $30,000. Puget Sound bids vary with the home, the access and how far the growth has spread, so treat any single figure as a starting point rather than a quote.

What drives the price up or down?

• Square footage affected. EPA treats roughly 10 square feet, about a 3-by-3-foot patch, as the size a homeowner can usually handle. Past that, professional work and containment become more likely, and the per-foot pricing adds up.
• Porous materials. EPA notes that porous materials such as ceiling tiles and carpet may need to be thrown away when moldy. Removal and disposal cost more than cleaning hard surfaces.
• Containment and air handling. Larger jobs need plastic barriers and negative air to keep spores out of clean rooms. Heating ducts are a separate issue: EPA says not to run an HVAC system you know or suspect is contaminated, and duct work is one of the pricier lines on Angi's Seattle list.
• Moisture that is still active. Mold work only holds up if the water source is fixed. A bid that skips the leak, the bath fan or the crawl space drainage may look smaller but rarely lasts.
• Season and drying time. From October through April, Seattle's damp air means wood and drywall dry slowly. Dehumidifiers may need to run longer before a crew can close things up.
• Testing before and after. An inspection and clearance check are often billed separately, sometimes by a different firm.

What about repairs after the mold is gone?

Remediation removes and cleans. Putting the room back together is often a separate line item or a separate contractor. Angi's Seattle cost guide lists related repairs at $825 to $2,400 for drywall, $650 to $2,150 for carpet and $175 to $450 for flooring. When you compare bids, check whether rebuild is included. Two quotes can differ by thousands simply because one stops at bare studs and the other includes new drywall, tape and paint.

Should you pay for an inspection first?

If the mold is visible and the cause is obvious, such as a leak under a sink that has since been fixed, you may not need a separate inspection. EPA says that in most cases, when mold is visible, sampling is unnecessary. Paying for a mold inspection in Seattle makes more sense when you smell mold but cannot find it, when the moisture source is unclear, or when the job looks large. Angi's 2026 national data puts a normal inspection at $303 to $1,044. Our guide on the difference between inspection and testing explains which one fits which situation.

After a large job, a clearance check by someone other than the remediation crew gives you an independent answer on whether the work is done. Angi recommends using separate companies for testing and removal. Washington law does not require that split, but it removes the obvious conflict of interest. See what post-remediation testing involves before you schedule the final walk-through.

How to compare Seattle mold bids

1. Get at least two or three written bids, as Washington L&I's Hire Smart steps recommend, and ask each company to state the square footage, the materials to be removed and the containment plan.
2. Confirm the company is registered with Washington L&I as a construction contractor. Washington has no state mold license or certification, but anyone who bids on or performs repair work on a building counts as a contractor under RCW 18.27.010. Check the registration on L&I's Verify a Contractor tool, which also shows bond claims and citations.
3. Ask what is excluded: rebuild, sales tax, disposal fees, permits and testing.
4. Pay in stages as phases are completed rather than all up front, and get changes in writing.
5. Be wary of any bid that relies on spraying a coating over damp wood. EPA says not to paint or caulk over mold.

Our guide to checking a mold company in Washington walks through those steps in more detail. If you are wondering who pays, read whether homeowners insurance covers mold in Washington before you sign.

Prices outside the city

The figures above come from Angi's Seattle page. Suburbs and nearby cities use the same pool of companies, so bids are often similar, but drive time, access and housing stock all shift the number. If you live east of the lake, see mold remediation in Bellevue; to the south, see the Tacoma service page. For everything in one place, the Seattle mold remediation page covers what a full job involves.

Can you save money by doing it yourself?

For small areas, yes. EPA says a homeowner can usually handle mold covering less than about 10 square feet, and the Washington Department of Health gives the same threshold. Dry the area, fix the leak, clean hard surfaces, and throw out porous items that stay moldy. Past 10 square feet, with mold in hidden places, or after water contaminated by sewage, DOH says to consider hiring a professional. People with asthma or weakened immune systems should stay away from moldy areas, and anyone with health concerns should talk with a health professional. The least expensive job is the one you never need: drying water damage within 24 to 48 hours, running bath fans, and keeping indoor humidity below 60 percent, as EPA advises.