Indiana contractor licenses: three state programs and a lot of local rules

Indiana keeps its trade licensing narrow. The Indiana Professional Licensing Agency (IPLA) lists plumbing, home inspectors, manufactured home installers and a few other professions on its professions page. It does not list general contractors, roofers, electricians or HVAC technicians. Pesticides sit with a different office, the Office of Indiana State Chemist at Purdue. Everything else is handled by the county or city where the job is. This page sorts the trades into those groups. Our Indiana startup guide covers the LLC, DBA, workers' comp exemption and call recording side.

What the state licenses and who issues it

"No state license listed" means we found none on IPLA's professions page in October 2026. It does not mean no one regulates the work. Many Indiana cities and counties do.

Plumbing: a state license with a misdemeanor attached

Indiana Code 25-28.5 governs plumbing. It is unlawful to act as a plumbing contractor or journeyman plumber without a license from the commission, and doing so, or even advertising as one, is a Class A misdemeanor. Continuing to work after a license has expired is a Class B misdemeanor. Helpers, laborers and registered apprentices who work for a licensed plumber and do not present themselves to the public as plumbers are not covered by the licensing requirement.

The route works like this:

• Apprentice. Anyone 17 or older can register as an apprentice with a signed statement from a licensed employer. The apprentice works under the direct, personal supervision of a licensed contractor or journeyman.
• Journeyman or contractor. An Indiana resident applicant needs either four years in a commission-approved apprenticeship or a notarized statement of at least four years of experience in the trade, then passes the commission's exam. Plumbing contractors must be at least 18, and the license can go to a corporation that meets the chapter's extra requirements.
• Reciprocity. The commission grants a license without an exam to someone licensed in another state if that state's requirements were substantially equal when the license was issued and the other state offers Indiana licensees the same privilege. The category must match.

The statute also sets an advertising rule (IC 25-28.5-1-35). A plumbing contractor's license number must be recognizably displayed in all written or printed advertising for plumbing services and on all vehicles used to provide plumbing services. The commission's rules (860 IAC 1-4) say the number must be large enough to read and close to the advertisement, and must appear on each side of a vehicle that carries the contractor's or business name. Add it to your printed ads, signs and trucks, and confirm with the commission how it treats a website.

An owner-occupant of a dwelling of eight or fewer units may install, alter or repair the plumbing in that dwelling without a license. The statute's definition of plumbing excludes well drilling, pumps and pressure tanks that are incidental to a well system, and the sale and installation of water softening equipment. For plumbing licensing elsewhere, see our plumber licensing guide.

Pesticides and lawn fertilizer: the State Chemist rules

This is the part that catches lawn care, landscaping and pest companies. The Office of Indiana State Chemist (OISC) administers Indiana's pesticide laws (IC 15-16-4 and 15-16-5) and enforces the federal rules in the state. It says any business that applies restricted-use pesticides, general-use pesticides or fertilizer material to another person's property for hire must hold a business license. The business must carry liability insurance and employ at least one for-hire commercial applicator who is fully certified in the categories in which the business operates.

The insurance figure is specific. OISC says a pesticide application business needs a minimum of $300,000 general liability combined single limit for bodily injury and property damage, shown on a certificate of insurance issued in the business name that will print on the license. A wood-destroying pest inspection business (Category 12) needs $300,000 for property damage.

Individuals have separate paths:

• Certified applicator. Pass a written Core exam, then a category exam. Candidates may attempt any exam up to three times in a twelve-month period. Certification lasts five years and expires December 31 of the fourth year after the year of qualification. After certification you must be licensed to buy, use or supervise pesticides, and the license renews each December 31.
• Registered technician. An employee at least 18 can apply a general-use pesticide for hire if they are a certified and licensed applicator or a registered technician who has finished a mandatory training option.
• Fertilizer for hire. The applicator must work for a licensed business and be certified and licensed or a registered technician. To spread fertilizer on turf for hire, an applicator must pass the Category 3b written exam, according to OISC's 2024 requirements document, so confirm with OISC whether any alternative routes have changed since. Category 14 covers agricultural lands.
• Termite and wood-destroying pest work. For-hire certification in Category 7b or Category 12 also requires a practical hands-on training program approved by the State Chemist.

Category 3a covers ornamental plantings and related areas such as driveways, sidewalks, residential parking areas, landscape beds and fence lines. Category 3b covers turf. OISC lists 15 continuing certification hours for 3a and 20 for 3b if you renew by credits rather than retesting. See our pest control license guide for the national picture, and our lawn care startup guide for Iowa to see how a neighboring state sets up the same job.

Septic work is registered by the county

Indiana does not run a single statewide septic installer license. The Indiana Department of Health publishes a recommended county ordinance, and its installer section says an installer must register with the county health department before installing, replacing, altering, repairing or abandoning any residential or commercial on-site sewage system in that county. Registration in the model language requires an application, a fee set in the county's fee ordinance, and proof of certification by passing the county's exam (or another approved entity's exam) or by showing a current registration in another Indiana county. The model also requires a registered installer to be on site during the work and responsible for it.

Because each county adopts its own ordinance, the fee, the exam and the renewal date can differ from one county to the next. Call the health department in every county on your route before you quote a system.

Home inspectors have a state board

Indiana Code 25-20.2 applies to anyone who conducts home inspections for compensation, and a Home Inspectors Licensing Board sits inside IPLA. The article carves out a few people: code enforcement officials, registered architects and professional engineers, licensed plumbers acting within their license, licensed real estate brokers and appraisers acting within their license, and certain others. If you are adding inspections to a remodeling or pest business, the article is the place to check whether your existing credential already covers it.

The home improvement contract rule and the local layer

Indiana's home improvement statute, IC 24-5-11, applies to residential property with one to four units used at least partly as the consumer's dwelling. A real property improvement contract is any agreement, oral or written, whose price exceeds $150. For those contracts, the supplier must give the consumer a completed contract before it is signed, and the contract must include:

• the supplier's name and address, plus an email address the supplier uses to talk to consumers;
• name, phone number and email for each person to whom problems can be directed;
• a reasonably detailed description of the work, the price, and the approximate start and completion dates;
• a statement of whether any subcontractor, vendor or other third party will furnish labor, materials or equipment.

The chapter also says that if a license or permit is needed for any part of the work, the contract must be conditioned on the right party getting it before work starts. That wording matters because Indiana's local permits do much of the work other states hand to a state board.

For anything not listed above, ask the building or permit office in each city and county where you work. Our contractor licensing boards table links the official starting point for each state, and the contractor license guide shows how state and local layers fit.

Unlicensed trades and the paperwork they still carry

Mowing without chemicals, house cleaning, pressure washing and junk removal do not appear on IPLA's profession list, and the pesticide office does not regulate them unless you apply a pesticide or fertilizer. You still need the following. The Department of Revenue says a business selling goods or tangible personal property must register to collect Indiana's 7 percent sales tax and receives a Registered Retail Merchant Certificate. Ask the department which of your charges it treats as taxable, and keep labor and materials on separate invoice lines. If you hire people you must insure their workers' comp, and Indiana Code 22-3-2-14.5 sets up an independent contractor exemption certificate, issued through the Department of Revenue and the Worker's Compensation Board, with a fee listed on the current application form (State Form 45899). Confirm the fee and renewal terms before you rely on it. See workers' comp by state for the comparison.

What to do first

1. List every service you plan to sell. Mark any that involve plumbing, pesticide, fertilizer, septic or inspection.
2. For pesticide or fertilizer work, book the Core and category exams with OISC and ask your insurer for a certificate at the $300,000 level before you apply for the business license.
3. Call the building department in the first three towns you will work in and ask what they require for your trade.
4. Rewrite your standard estimate so it meets the home improvement contract list above.

Treat this as general information and not legal advice. Fees, exam dates and ordinances change, and we read the facts above in October 2026, so confirm each one with the agency before you act.

Frequently asked questions