Licensing Guides
Iowa Septic License: How to Become a Septic Contractor in Iowa
Septic, IA
September 21st, 2026
Table of Contents
Septic License Requirements in Iowa
We all need safe, reliable sewage management for our homes and businesses. Those homeowners and businesses that rely on septic tanks, also known as on-site sewage facilities (OSSF), depend on people who know how to install and maintain those systems.
Across Iowa, many homes and properties without access to a public sewer rely on private sewage disposal systems, also known as onsite wastewater treatment systems, to manage their wastewater.
According to the Bureau of Labor Statistics (BLS), there are 30,650 septic tank servicers and sewer pipe cleaners nationwide, and Iowa employs 630 of them. The projected growth rate nationally is expected to be 8% from 2024 to 2034, with about 2,900 job openings projected each year. In the state of Iowa, according to CareerOneStop, the U.S. Department of Labor’s job search website, the projected growth rate is 14% for septic tank servicers and sewer pipe cleaners.
If you’re thinking about starting a septic business or working in this field, you need to know the requirements in your state or local jurisdiction. This guide will help you determine what you need before you get started in Iowa state.
Is a license or certification required to do septic work in Iowa? Yes — but which credential you need depends on the work. Iowa requires a state-issued credential to commercially pump and clean septic tanks (Commercial Septic Tank Cleaner license), to inspect systems at the time of property transfer (Time of Transfer Inspector certification), and to operate water and wastewater systems (Drinking Water and Wastewater Operator certification). Many counties also require installers to hold the Certified Installer of Onsite Wastewater Treatment Systems (CIOWTS) credential. Working without a required credential can lead to enforcement action, including civil penalties. Under Iowa Code section 455B.172, only a licensed person may commercially clean septic tanks, and only a DNR-certified inspector may perform time-of-transfer inspections.
Types of Septic Licenses in Iowa
Statewide septic licenses in Iowa include:
Time of Transfer Inspector: Required to assess septic systems before the sale or deed transfer of properties (time of transfer inspections). Requires two years of relevant experience or an approved course, plus passing a DNR exam. Only a DNR-certified inspector may perform these inspections (Iowa Code 455B.172(11)).
Commercial Septic Tank Cleaner: Required for professionals or firms engaged in septic tank pumping and cleaning. Licensed by the Iowa DNR NPDES Section under 567 Iowa Administrative Code Chapter 68. No exam is required — licensing is by application and fee.
Drinking Water and Wastewater Operator: Required for water and wastewater operators. Requires passing a DNR exam.
In addition, many counties impose their own licensing or registration requirements. In fact, 25 Iowa counties require a Certified Installer of Onsite Wastewater Treatment Systems (CIOWTS) credential from the Iowa Onsite Waste Water Association (IOWWA). The CIOWTS credential covers installing onsite wastewater treatment systems and requires passing the IOWWA exam; an installation course is required if you have less than one year of installation experience.
Steps to Get a Septic License in Iowa
To obtain a Time of Transfer Inspector certification from the Iowa DNR, follow these steps:
Obtain two years of experience in the operation, installation, inspection, design or maintenance of private sewage disposal systems (onsite wastewater treatment or septic systems), or complete the "Basics of Onsite 101" class offered by the Onsite Wastewater Training Center of Iowa or an equivalent class approved by the Iowa DNR.
Register and complete the eligibility exam application process.
Complete the Time of Transfer Inspector Training offered by the Des Moines Area Community College (DMACC) Onsite Wastewater Training Center of Iowa. This incurs a $300 fee.
Pass the exam administered after the training course.
Pay a $300 certification fee to the Iowa DNR.
To obtain a Commercial Septic Tank Cleaner certification, follow these steps:
Complete the license application by contacting the Iowa DNR through its Commercial Septic Tank Cleaner licensing page.
Pay a fee of $100 for the first truck, and $50 per additional truck.
To obtain a Drinking Water and Wastewater Operator certification, follow these steps:
Apply for exam eligibility.
Once you receive notification of eligibility, register for and pass the exam (incurs $30 fee).
Pay $80 certification fee (may be prorated based on when in the two-year licensing cycle you apply).
To obtain a CIOWTS credential from the IOWWA, follow these steps:
Complete the test application.
If you have less than one year of experience installing septic systems, attend the Installation Overview Course prior to taking the test. The course and test are held in the same two-day event.
Pass the exam.
Be sure to check septic permit application requirements in each locality you intend to work.
Benefits of Getting a Septic License in Iowa
There are many benefits to earning your Iowa septic credential:
Most important, it is required by law to perform regulated septic work in Iowa, from commercial tank cleaning to time-of-transfer inspections.
A credential is proof of your experience and skill.
It lets you legally operate and advertise a septic business.
It lets you pull permits and pass local inspections.
It opens the door to more jobs as demand for skilled septic professionals grows.
It increases your earning potential.
It protects both your business and your customers.
What Is the Mean Wage for a Septic Professional in Iowa?
The mean annual wage for septic tank servicers and sewer pipe cleaners in Iowa is $57,200, according to the U.S. Bureau of Labor Statistics — higher than the national mean of $53,500. In Iowa, the lowest-paid 10% of these workers earn about $40,650 a year, while the highest-paid 10% earn about $72,660. Pay generally rises with experience, certifications, the region where you work, and whether you own the business.
The terms "mean wage" and "median wage" can be confusing. Here is the difference:
Mean wage is the mathematical average.
Median wage is the midpoint at which half of workers earn more and half earn less, and is often a better indicator of typical pay. In Iowa, the median annual wage for this occupation is about $57,980.
How Much Does It Cost to Get a Septic License in Iowa?
The cost depends on credential type:
Time of Transfer Inspector: $600
Commercial Septic Tank Cleaner: $100 for the first truck, and $50 per additional truck
Drinking Water and Wastewater Operator: $80
CIOWTS: $184 to $229 (depending on Basic/Advanced credential and membership)
Additional permit fees may apply, depending on the county.
What Business Owners Need to Know
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Location-specific service history, including recorded calls, accessible from the mobile app.
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How Long Does it Take to Get a Septic License in Iowa?
The Time of Transfer certification requires two years of experience or completing a course. The CIOWTS credential requires one year of experience or completing a course. Other license types simply require passing an exam.
Iowa Septic Training Programs and Schools
The DNR and IOWWA partner with Des Moines Area Community College for training.
Iowa Septic Licensing Exam Details
There is an exam required for each license type except Commercial Septic Tank Cleaner. Time of Transfer and Drinking Water and Wastewater Operator exams are issued by the DNR, with Time of Transfer testing delivered through the DMACC training course. IOWWA administers its own CIOWTS exam: the Basic Level exam is 75 multiple-choice questions with a two-hour time limit, and the Advanced Level exam is 125 questions with a three-hour time limit; a score of 70% or higher is required to pass either level. Helpful resources, including a study guide, are listed on the IOWWA certification page.
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How Can I Prepare for the Septic License Exam in Iowa?
How you prepare depends on the credential you are pursuing.
For the CIOWTS exam, review the study materials and resources on the IOWWA certification page. The Basic Level exam is 75 multiple-choice questions (two hours) and the Advanced Level exam is 125 questions (three hours); you need 70% or higher to pass. If you have less than a year of installation experience, the Installation Overview Course held before the test is your main preparation.
For the Time of Transfer exam, the test is given at the end of the two-day training course run by the DMACC Onsite Wastewater Training Center of Iowa. Contact DMACC for the current reference materials and exam format.
For any of these exams, the best preparation is to work through the course materials, complete any available practice questions, and get plenty of rest before test day.
Who Issues Septic Licenses in Iowa?
In Iowa, local board of health departments or environmental health divisions regulate onsite wastewater treatment systems (also known as private sewage disposal systems) serving four homes or fewer or less than 15 people, while the Iowa Department of Natural Resources regulates larger, public systems per the Iowa Administrative Code (IAC). To support counties in their regulation efforts, the DNR hosts an annual training for new county sanitarians. This helps ensure proper water quality and public health.
Does My Iowa Septic License Work in Any Other State?
No. Iowa septic credentials are state-specific and do not automatically transfer to other states. If you plan to work in another state, you will need to apply under that state’s rules. Likewise, an out-of-state credential does not automatically qualify you in Iowa. The one limited exception is the Drinking Water and Wastewater Operator certification, for which the DNR reviews out-of-state credentials on a case-by-case basis, as covered below.
Does Iowa Reciprocate Septic Licenses?
Iowa offers only partial reciprocity for septic credentials. There is no general reciprocity for the Time of Transfer Inspector, Commercial Septic Tank Cleaner, or CIOWTS credentials — you must meet Iowa’s requirements directly. The only credential eligible for reciprocity is the Drinking Water and Wastewater Operator certification, which the DNR reviews case by case, depending on whether the applicant's out-of-state certification aligns with Iowa's standards and requirements. Applicants should request a reciprocity review through the Iowa DNR's Water and Wastewater Operator Certification program.
National Septic Certifications
Other certifications can help you demonstrate your proficiency to potential employers and clients. The National Association of Wastewater Technicians and The National Onsite Wastewater Recycling Association offer certifications. Those and other professional certifications are not required but can add to your marketability and therefore increase your opportunity to make more money.
Other Requirements Unique to Iowa
Iowa splits septic oversight between local and state authorities: county boards of health or environmental health divisions regulate onsite systems serving four homes or fewer (or fewer than 15 people), while the Iowa DNR regulates larger systems. Because of this, requirements vary by county. In particular, 25 Iowa counties require installers to hold the Basic Level CIOWTS credential: Benton, Black Hawk, Bremer, Buchanan, Butler, Cedar, Chickasaw, Clayton, Dallas, Delaware, Floyd, Grundy, Hamilton, Hardin, Iowa, Jasper, Jones, Linn, Marion, Scott, Story, Tama, Warren, Washington, and Winneshiek. IOWWA advises checking with your county sanitarian for specific requirements.
Are There Septic Scholarships in Iowa?
Yes. Iowa’s Future Ready Iowa Last-Dollar Scholarship helps cover tuition up to an associate degree for high-demand fields, and several water and wastewater programs — including Water Environment Technology and wastewater treatment diplomas — are eligible at Des Moines Area Community College for the 2026-27 aid year. All applicants start by filing the FAFSA. In addition, all incoming DMACC Water Environmental Technology students receive a $1,000 industry-funded scholarship, renewable for a second year for students in good standing. Because eligible programs and deadlines change annually, confirm current details with the school.
How Can Someone Verify My Septic License in Iowa?
Homeowners and employers can confirm a Time of Transfer Inspector’s certification through the Iowa DNR’s public Onsite Septic Inspector list, which the DNR is required to maintain under Iowa Code 455B.172. Submitted inspection reports can also be searched in the DNR’s Time of Transfer database. Commercial Septic Tank Cleaner licenses are issued by the Iowa DNR’s NPDES Section, so verification questions about those licenses can be directed to the DNR.
When Can a Septic License Get Suspended in Iowa?
The Iowa DNR can discipline certified professionals for causes such as professional incompetence, filing false statements, or repeated violations of the rules. Under 567 Iowa Administrative Code 69.2(6), sanctions can include civil penalties of up to $1,000, probation, suspension, or revocation of a certificate. A certified inspector who fraudulently files a time-of-transfer report faces a $5,000 civil penalty and a one-year suspension under Iowa Code 455B.172.
Note: The information above should not be considered legal advice.
What Are the Penalties for Unlicensed Septic Work in Iowa?
Doing regulated septic work without the required credential is illegal in Iowa. Commercially cleaning or pumping septic tanks without a DNR license violates Iowa Code 455B.172 and carries a civil penalty of up to $250 for each day of violation, with each day treated as a separate offense. Only a DNR-certified inspector may perform a time-of-transfer inspection, and a county recorder cannot record a property deed without a certified inspector’s report. The DNR director can also issue cease-and-desist orders and refer violations to the attorney general for injunctive relief or additional penalties under Iowa Code 455B.175.
Note: The information above should not be considered legal advice.
Do I Need to Renew My Iowa Septic License?
Yes, Time of Transfer, Drinking Water Wastewater Operator, and CIOWTS credentials must be renewed every two years. The Commercial Septic Tank Cleaner certification must be renewed annually.
Continuing Education
IOWWA requires 12 hours of continuing education in the onsite wastewater industry every two years. CEU opportunities are listed on its website. In addition, the DNR requires a minimum of 12 hours of continuing education each renewal cycle for Drinking Water Wastewater Operators and Time of Transfer inspectors.
Resources
You can stay up to date on all septic industry news several ways:
Check top septic blogs, including ServiceTitan’s blog.
Read about the latest industry trends, and discover ideas on how to grow your septic business.
Listen to top septic podcasts like ServiceTitan’s “Toolbox for the Trades” podcast.
The states have licensing requirements for other trades, too. You can find out more about how to get an HVAC, plumbing, or electrical license in Iowa, or in any of the other 49 states and the District of Columbia through the ServiceTitan Licensing Hub.
