Septic Inspection Certification: Become a Septic Inspector
How to become a septic inspector: NAWT certification, the state programs in MA, AZ, DE, NH, RI, WA, MN and PA, and how to add septic to a home inspection.
Short answer: There is no single national septic inspector license. The main private training route is the National Association of Wastewater Technicians (NAWT) inspector certification, and several states add their own rules: Massachusetts, Arizona and Delaware require a state-approved or licensed inspector when a property sells, and Minnesota certifies its own septic inspectors. Start with your state's rule, because it decides which course and exam count.
Septic inspection sits at the edge of home inspection. The InterNACHI Standards of Practice, for example, say the inspector is not required to "inspect wastewater treatment systems, septic systems or cesspools" (Sec. 3.2). Buyers of rural and waterfront properties still need someone to look at the system. That gap is the opening for a septic inspector, whether as a whole business or as an add-on to home inspections.
The rules vary a lot from state to state. In some states you can inspect after a two-day course. In others, the state names who may inspect, what form to use and how fast the report goes to the regulator. This guide covers the NAWT route, the state programs we confirmed, and how to add septic to a home inspection business.
Is there a national septic inspector license?
No. There is no federal septic inspector credential. The credential most often referenced is a private one, the NAWT inspection certification, and some states build their own programs on top of it or instead of it.
States regulate septic inspection in two ways:
- An inspection at sale. The state requires the system to be inspected when the property changes hands.
- Who may inspect. The state approves, licenses or certifies the inspector, often with its own exam.
Some states do one, some do both, and many do neither at the state level and leave it to counties. Check with your state's environmental or health agency and your county before you advertise.
NAWT inspector certification
NAWT describes its Inspection Standards Certification Course as "a two-day, in-depth training program" for professionals inspecting onsite wastewater systems. It covers inspections for transfer of title, operations and maintenance, and regulatory compliance. NAWT says the course focuses on "evaluating system components, interpreting findings, and reaching defensible conclusions," and ends in "a comprehensive exam." Passing earns NAWT certification. NAWT lists the audience as "inspectors, pumpers, installers, and regulatory officials."
NAWT's course page does not publish prerequisites, a price, a certification term or renewal rules. Courses are delivered through host organizations. One host's February 2026 online class listed two days at $350 for members and $450 for non-members, and said "NAWT Certificates require 8 CEU hours every 2 years." Mohave County, Arizona, gives the same 8-hours-every-2-years figure for NAWT-trained inspectors. The host also said that from January 2026 certificate holders must retake the updated two-day course and exam (those certified or renewed in 2025 have until January 2028). We could not confirm the renewal or retake rules on a NAWT page, so check them with NAWT or your course host before you enroll.
NAWT also runs O&M, installer, vacuum truck technician and design courses. Those are separate credentials.
State septic inspection rules we confirmed
As of September 2026, from each state's regulation, statute or agency page. Rules change, and local rules can add to them.
| State | Inspection at sale | Who may inspect |
|---|---|---|
| Massachusetts (Title 5, 310 CMR 15.000) | Required within 2 years before sale (3 years if the system is pumped annually; up to 6 months after sale if weather prevents it). Transfers between certain family members and refinancing are exempt | MassDEP-approved System Inspectors only, on the MassDEP form, report within 30 days |
| Arizona (ADEQ) | Transfer-of-ownership inspection within 6 months before transfer; buyer files a Notice of Transfer within 15 days | Certified inspector under R18-9-A316: training from an ADEQ-recognized course plus a license in a listed category. Mohave County says NAWT is currently the only trainer ADEQ recognizes |
| Delaware (7 DE Admin. Code 7101) | System pumped (Class F) and inspected (Class H) before sale; reports to DNREC within 72 hours | Class H licensee |
| New Hampshire (RSA 485-A:39) | Developed waterfront property with a system within 250 feet of the reference line: buyer engages an evaluator before transfer | NH licensed septic system evaluator |
| Rhode Island (23-19.15-12) | Cesspools replaced or connected to sewer within 12 months of sale; unknown systems inspected before sale | See the state rule |
| Washington (WAC 246-272A-0270) | From February 1, 2027, owners obtain an inspection at transfer. Snohomish County's requirement took effect November 1, 2026 | Third-party inspector authorized by the local health officer |
| Minnesota (MPCA) | Set locally (not verified at state level) | MPCA-certified inspector |
| Pennsylvania | No statewide sale requirement found. Penn State Extension describes the PSMA/NOF real estate inspection as separate from regulatory inspections, which some municipalities require every 3 to 5 years | PSMA/NOF-101 certification is the usual real estate route |
State inspector credentials in more detail
| State | Credential | Training and exam | Renewal and CE |
|---|---|---|---|
| Massachusetts | MassDEP-approved System Inspector | NEIWPCC class plus written exam (professional engineers, certified health officers and registered sanitarians can use pre-approval) | Every 3 years, $100; 10 contact hours from the second renewal |
| Arizona | Transfer-of-ownership inspector | ADEQ-recognized training (NAWT, per Mohave County) plus a license in a listed category | 8 hours CE every 2 years, per Mohave County |
| Delaware | Class H inspector | Training certification (for example NAWT or PSMA), DNREC exam at 70%, first 3 inspections supervised | Annual license, 10 hours training a year |
| Minnesota | MPCA Basic Inspector | Five courses (introduction, installing, basic design, inspecting, soils), each with an exam at 70%, plus field experience: 15 inspections, and observing 5 site evaluations, 5 installations and 5 pump-outs | 3-year certification; 18 CE hours, 6 of them in soils |
| Pennsylvania | PSMA/NOF-101 | 15 hours with field practicum and exam | Valid 2 years; PSMA lists no CE requirement |
Three things stand out.
Arizona ties you to NAWT. Its rule requires training from a course ADEQ recognizes, and Mohave County's guidance says NAWT is currently the only one, so a different course is unlikely to qualify you there. Confirm with ADEQ.
Delaware and Massachusetts run their own exams. A NAWT certificate helps in Delaware as the training step, but you still need the DNREC exam and three supervised inspections. Massachusetts uses a class and exam that NEIWPCC runs for the state.
Washington's rule is new. Transfer inspections become required statewide on February 1, 2027. Snohomish County's requirement took effect November 1, 2026: sellers there need a full septic inspection by a certified septic contractor within the past 12 months before closing. The inspector must be authorized by the local health officer, so the path runs through your county.
Step by step: becoming a septic inspector
- Find your state and county rule. Is an inspection required at sale? Who may perform it? Is there a state form?
- Take the training your state recognizes. NAWT in Arizona, NEIWPCC in Massachusetts, the MPCA program in Minnesota, PSMA in Pennsylvania. In states without a program, NAWT is a widely used option.
- Pass the exam for that program, plus any state exam (Delaware and Minnesota both set 70%).
- Apply for the state credential where one exists, and complete any supervised inspections (three in Delaware).
- Arrange pumping. Some inspections need the tank pumped, and Delaware requires a Class F pumper. Build a relationship with a local pumper.
- Check your insurance. Confirm your E&O covers septic work. See home inspector insurance.
- Keep CE current. Hours vary: 10 a year in Delaware, 18 per three years in Minnesota.
Adding septic to a home inspection business
For a home inspector, septic is a natural add-on on rural and semi-rural properties, and a requirement in the states above. Before you add it, run the numbers on their own, as in how to price ancillary inspection services.
| Start-up item | Where the figure comes from | Notes |
|---|---|---|
| NAWT inspector course | Course host (example: $350 member / $450 non-member, February 2026) | Price set by each host; confirm |
| Massachusetts System Inspector renewal | MassDEP | $100 every 3 years |
| State exam and license fees (DE, MN) | DNREC, MPCA | Check the agency's current fee |
| Equipment (probe, locating tools, camera) | Your suppliers | Varies |
| Pumping | Local pumper | Agree up front who orders and pays for it |
| E&O coverage for septic | Your insurer | Ask for a quote |
A few practical points:
- Know where your home inspection stops. A home inspection may note visible wastewater problems inside the house. Evaluating the tank and drainfield is the septic inspection. Keep the two separate in your agreement and your report.
- Pair it with sewer scopes and wells. Properties on septic may be on a private well too. The guides to sewer scope inspections and well inspections cover the related services.
- Follow the state form where one exists. In Massachusetts, the inspection goes on the MassDEP form. Your own report does not replace it.
- Watch the deadlines. Thirty days to report in Massachusetts, 72 hours in Delaware. Build them into your scheduling.
Delivering a separate septic report in Binsr
A septic report has a different reader from a home inspection report, and may need to go to parties who do not need the rest of the house.
In Binsr, one inspection can produce multiple reports, each with its own template. The home inspection and the septic inspection from the same visit go out as separate reports, and you can lock or hide either report from the client until it is ready, for example while the pumper finishes. Templates are fully configurable, so a septic template can carry its own sections for the tank, baffles, distribution box and drainfield, with photos attached to each finding.
Where a state requires its own form, such as the MassDEP form in Massachusetts, file that form as the state requires.
How long it takes
- NAWT course: two days of training plus the exam.
- Pennsylvania PSMA/NOF-101: 15 hours including a field practicum.
- Delaware Class H: training, the DNREC exam, then three supervised inspections before you work alone.
- Massachusetts: the NEIWPCC class and exam, then MassDEP approval.
- Minnesota: five MPCA-required courses with an exam each, plus the field experience for Basic Inspector.
If you are not yet a home inspector and want to offer both, add the time for your state's home inspector license. See the pillar guide and the license requirements by state.
Frequently asked questions
Sources and verification
- Massachusetts Department of Environmental Protection, Buying or selling property with a septic system
- Massachusetts Department of Environmental Protection, System Inspectors and Soil Evaluators: training, licensing and renewal
- Arizona Department of Environmental Quality, Onsite wastewater Notice of Transfer and inspection (revised August 5, 2026)
- Mohave County, Determining the qualifications of an inspector for the transfer of ownership inspection program
- Delaware Administrative Code, Title 7, 7101
- Delaware DNREC, Groundwater discharge licenses
- New Hampshire RSA 485-A:39
- Rhode Island General Laws 23-19.15-12
- Washington Administrative Code 246-272A-0270
- Snohomish County Health Department, Property Transfer
- Minnesota Pollution Control Agency, SSTS individual certification
- NEIWPCC, Title 5 certification
- National Association of Wastewater Technicians, Training courses
- Pennsylvania Septage Management Association, Certification training
- InterNACHI, Home Inspection Standards of Practice
- Penn State Extension, On-lot septic system inspections during real estate transactions
- CPOW, NAWT inspector class, February 2026 (course host example)
Keep reading
- How to become a home inspector
- Adding sewer scope inspections to your business
- Well inspections and water testing as an add-on
- How to become a mold inspector
- How to price ancillary inspection services
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