Does a Mold Remediation Company Need a License?
It depends on where the house is. A handful of US states, including New York, Texas, Florida and Louisiana, require a state license to assess or remediate mold above a set size, while most states and every Canadian province have no mold-specific license at all. Where no license exists, the work is still shaped by published remediation guidelines, general contractor rules and, in some places, landlord laws.
That patchwork is why two quotes for the same basement can look so different. One company may be working under a licensing regime with mandatory paperwork, the other under no rules beyond its own habits. Knowing which situation applies to your address tells you what to expect and what to ask for.
US states with mold licensing laws
The states below have their own licensing programs. Rules change, so confirm the current version with the state agency before you sign anything.
New York. Article 32 of the New York State Labor Law, in force since 2016, requires anyone who performs mold assessment, remediation or abatement on a project larger than 10 square feet to hold a license from the state Department of Labor. The law also separates the two roles: the company that writes the assessment and remediation plan cannot be the company that does the cleanup on the same project. In New York City, Local Law 61 of 2018 adds that mold work in residential buildings with 10 or more apartments has to be done by state-licensed firms once it passes the size threshold.
Texas. The Texas Mold Assessment and Remediation Rules, now administered by the Texas Department of Licensing and Regulation, apply to projects of 25 contiguous square feet or more. Assessors and remediators are licensed separately, the same firm generally cannot do both on one job, and a licensed assessor has to write the remediation protocol and check the work afterward. When a project passes clearance, the owner is supposed to receive a Certificate of Mold Remediation, which is worth keeping for insurance claims and a future sale.
Florida. Florida licenses mold assessors and mold remediators through the Department of Business and Professional Regulation under Chapter 468 of the Florida Statutes. Jobs under 10 square feet are generally exempt, and there are exemptions for some other licensed trades working within their normal scope.
Louisiana. Mold remediation in Louisiana falls under the State Licensing Board for Contractors, which issues a specific mold remediation license.
A few other states and cities have registration rules, disclosure requirements for landlords, or licensing tied to schools and public buildings rather than private homes. If your state is not on the list above, assume there is no mold-specific license and focus on the hiring checks further down.
How Canada handles mold work
No Canadian province or territory issues a mold remediation license. Instead, the work is governed by a mix of guidance documents and general construction and workplace rules.
The guidance most companies point to includes the Health Canada material on mould in the home, the Canadian Construction Association's CCA 82 mould guidelines for the construction industry, and the mould abatement guidelines published by the Environmental Abatement Council of Canada (EACC). None of these is a law on its own, but they describe the containment, removal and cleaning steps a careful contractor follows, and they are often cited in contracts, insurance files and disputes.
Two other sets of rules can still apply:
- Construction licensing. When remediation includes tearing out and rebuilding drywall, flooring or framing, the rebuild part can fall under provincial contractor rules. In Quebec, renovation work on a building generally requires a Régie du bâtiment du Québec (RBQ) licence, so the company putting your basement back together should be able to show one.
- Workplace safety. Provincial occupational health and safety laws require employers to protect workers from biological hazards. That is why a crew working in a heavily affected attic wears respirators and uses containment, even though no mold-specific statute tells them to.
For rented homes, provincial tenancy law matters more than any remediation rule. Our post on landlord responsibility for mold in Ontario covers how that works in one province.
The size thresholds behind the rules
Almost every rule set uses square footage to decide how much process a job needs. The US EPA guide on mold remediation in schools and commercial buildings, which many residential contractors also follow, groups jobs roughly like this:
| Affected area | Typical category | What usually changes |
|---|---|---|
| Under 10 sq ft | Small | Often handled by the owner or general maintenance with basic protection |
| 10 to 100 sq ft | Medium | Limited containment, trained workers, more care with disposal |
| Over 100 sq ft | Large | Full containment, negative air pressure, professional oversight |
Licensing thresholds track those categories. New York and Florida start at 10 square feet, Texas at 25 contiguous square feet. For reference, 10 square feet is about the size of a single sheet of drywall cut down the middle, so a stain that covers the lower half of one basement wall can already be past the small category.
Hidden growth is the catch. A spot the size of a dinner plate on the surface can sit over a much larger patch inside the wall cavity, which is one reason an inspection usually comes before a firm price.
What to ask before hiring, licensed state or not
Whether or not your area has a license requirement, these questions separate a careful company from a quick one:
- Where is the moisture coming from, and who fixes it? Removing mold without stopping the leak, condensation or groundwater means paying twice. The quote should name the source.
- What is the scope in writing? Areas, square footage, materials to be removed, materials to be cleaned, and how the space will be contained.
- How is the rest of the house protected? Plastic sheeting, sealed doorways, air scrubbers with HEPA filters and negative pressure are normal for anything beyond a small job.
- What happens to removed material? It should be bagged inside containment and carried out sealed.
- How will you show the work is done? A visual check with moisture readings at minimum, and clearance sampling by an independent party when the job is large, disputed or tied to a sale.
- Which license or permit applies here? In a licensing state, ask for the license number and look it up on the state site. In Canada, ask about contractor licensing for any rebuild work.
If an inspection comes first, our mold inspection page explains what the visit covers, and the mold removal page outlines how a typical cleanup is staged.
Frequently asked questions
Can the same company inspect and remove mold?
In New York and Texas, the rules generally prevent one firm from acting as both assessor and remediator on the same project. Elsewhere it is allowed, and many homeowners prefer it because it saves a visit. If you use one company for both, ask for the scope in writing before work starts and consider an independent clearance check at the end.
Does a homeowner need a licensed contractor to remove a small patch of mold?
No licensing law covers a homeowner cleaning a small area in their own house. Under about 10 square feet, a careful owner with gloves, an N95 or better respirator and eye protection can usually handle surface growth on hard materials. Porous materials like drywall and carpet with visible growth are better removed than cleaned.
Is there a Canadian mold remediation certification worth looking for?
There is no government license, but several private training and certification bodies exist, and some contractors hold credentials from them. Treat a certification as one point in a company's favour rather than proof of quality, and still ask for the written scope, containment plan and clearance approach.
What paperwork should you keep after mold remediation?
Keep the inspection report, the written scope, photos before and after, invoices, and any clearance results or certificate the contractor or assessor provides. Insurers, buyers and home inspectors often ask for these, and in Texas the Certificate of Mold Remediation is the document buyers expect to see.
Get a written quote
Describe what you are seeing, roughly how large the area is, and where in the house it sits. A mold specialist who works in your area will review it and send a written scope and quote, with the moisture source named up front. Request your quote here.