Idaho contractor licenses: one registration, three licensed trades, and who else to ask

Idaho takes a lighter approach to general contracting than most states. It asks you to register, not to pass a trade exam, but it licenses electrical, plumbing and HVAC work through the Division of Occupational and Professional Licenses (DOPL), and it sends pesticide and septic work to other agencies. This page sorts the trades by who regulates them, with the dollar lines that matter. It is general information, so confirm each point with the agency. For forming the company, workers' comp and taxes, see our Idaho startup page.

Who has to register with the Idaho Contractors Board?

Anyone who does a construction job worth more than $2,000 in materials and labor, unless exempt. The Board's FAQ says the law requires registration, not licensure. The application asks for:

• your Social Security number (individuals) or employer tax ID (businesses), the business name and address, and the names of all owners
• a workers' compensation certificate from an Idaho-authorized insurer, or a statement of why coverage is not required
• a certificate showing general liability of at least $300,000 single limit, including products and completed operations
• a statement of construction type and a statement on any past denial or revocation of a license or registration

The first registration runs for 12 months after your next birthday and renews every year, with a notice about six weeks before expiration. Within 60 days of registering you must display the number at your place of business and your jobsite, and print it on advertising, contracts, building permits, letterhead, purchase orders and subcontracts. Your website counts as advertising, so keep the number in the footer.

Exempt from registering: architects, electrical contractors, engineers, surveyors, plumbers, manufactured home installers, service company contractors and HVAC installers, unless the work goes beyond their license. Employees paid wages, suppliers who do not install anything, and owners working on their own land who do not plan to sell within 12 months are also exempt. Our national contractor license guide compares this to states with full licenses.

What working unregistered costs

The Board's FAQ lists the consequences, and they stack:

• You cannot get building permits.
• You waive lien rights on real property.
• You lose the right to sue to collect under a contract that required registration.
• It is a misdemeanor, with a fine of up to $1,000, up to six months in county jail, or both.

Two more rules extend to the people you hire. You must get satisfactory proof that every contractor you engage is registered, or you risk your own lien rights. The Board can also revoke a registration for failing to keep the required insurance. Roofers and painters should read the same rules next to our roofing license overview.

The residential disclosure above $2,000

Before a general contractor signs a contract above $2,000 with a homeowner to build, alter or repair residential property, Idaho requires a written disclosure statement, with a signed receipt you keep. It tells the owner they can ask for lien waivers, proof of insurance, title insurance options, and a surety bond (up to the value of the project) at their own expense. A second disclosure is due before final payment or closing. It lists the subcontractors, suppliers and rental providers who supplied more than $500 of work or materials. Skipping the disclosures is an unlawful practice under the Idaho Consumer Protection Act, per the Board. If you quote online, add the disclosure to your estimate workflow.

Electrical, plumbing and HVAC have their own licenses

DOPL runs three more boards. Fees and terms below are as listed on each board's page in October 2026, and the electrical and HVAC boards are moving to biennial licensing on October 30, 2026, so fees and cycles may change.

For electricians, DOPL's journeyman application gives two routes: a board-approved four-year apprenticeship plus 8,000 hours of supervised electrical installation, or 16,000 hours of supervised work. Hours in appliance repair, motor winding or communications do not count. Out-of-state applicants can apply by reciprocity if the other state's verification shows the same hours and the license is active. The HVAC board lists the 2018 International Residential, Fuel Gas and Mechanical Codes as the adopted codes. See our guides on becoming an electrician and a plumber for the general path.

Pesticide spraying and septic work

The Idaho State Department of Agriculture licenses anyone who applies pesticides on another person's property for pay. Its licensing guide says Professional, Apprentice and Dealer licenses need an active general liability policy, and that applicants show competence by passing the approved exams, holding a good-standing letter from a reciprocal state, or completing approved training. Professional licenses cost $300 and last five years, expiring December 31 of the fifth year, with 40 recertification credits to renew. A Commercial Apprentice license costs $120, expires two years from issue and cannot be renewed. Plan on 8 to 10 business days of processing. Our pest control license guide covers the national picture.

Septic installation is a registration handled by Idaho's public health districts under DEQ's rules. DEQ says all septic systems must be installed by a licensed basic or complex installer, with one exception: a homeowner installing a standard system on their own property with no hired help. You turn in your exam certificate, the district's registration fee and proof of a $10,000 surety bond for basic or $30,000 for complex. Complex installers handle large soil absorption systems designed for at least 2,500 gallons per day.

Trades with no state license

As of October 2026, none of the agencies named on this page licenses lawn mowing, cleaning, pressure washing or junk removal as such, but a registration can still apply if the job becomes construction above $2,000. Cleaning, mowing and washing crews may also need a city business license, so check each city where you work. If you sell goods at retail, you need a seller's permit. Contractors who improve real property generally pay sales tax on materials and do not charge it to the customer, per the State Tax Commission. Workers' comp applies from your first employee. See our landscaping startup guide and pressure washing guide.

Frequently asked questions