Updated
Does Missouri require a septic license?
Yes. Missouri requires septic installers to hold a state credential issued by the Missouri DHSS Onsite Wastewater Treatment program. Missouri registers onsite system installers; no public download of the registry was found.
Who licenses septic contractors in Missouri?
Missouri DHSS Onsite Wastewater Treatment program.
Missouri's septic credentials:
- Registered basic installer
- Registered advanced installer
How to check a septic contractor's license in Missouri
- Missouri has no public statewide list of septic contractors.
- Ask the contractor for their local license or registration number and which county or town issued it.
- Call that county health department or town office to confirm it is current.
Septic permits in Missouri
A contractor license says who may do septic work; a permit authorizes a specific system. In Missouri, permits for new systems, replacements and most repairs come from the local health department or the state agency office that covers the property. Ask your installer to pull the permit and include the fee in the quote.
Licensed septic companies in Missouri
The Septic Guide lists 29 septic companies and licensed professionals in Missouri. This is what we could match as of October 2026, not an official count.
All septic companies in Missouri →
Missouri septic licensing: common questions
Do you need a license to install septic systems in Missouri?
Yes. Missouri requires septic installers to hold a state credential issued by the Missouri DHSS Onsite Wastewater Treatment program. Missouri registers onsite system installers; no public download of the registry was found.
Who issues septic licenses in Missouri?
The Missouri DHSS Onsite Wastewater Treatment program issues Missouri's septic credentials: Registered basic installer; Registered advanced installer.
How do I check a septic contractor's license in Missouri?
Missouri has no public statewide list of septic contractors. Ask the contractor for their local license or registration number and which county or town issued it. Call that county health department or town office to confirm it is current.
How many licensed septic contractors are in Missouri?
The Septic Guide lists 29 septic companies and licensed septic professionals in Missouri (data as of October 2026). This counts what we could match; it is not an official total.
Do you need a permit for a septic system in Missouri?
New septic systems, replacements and most repairs need a permit before work starts. The permit comes from the local health department or the state agency office that covers your property, and the permit, not the contractor license, is what authorizes a specific job.
Sources: Missouri DHSS Onsite Wastewater Treatment program; state license lists loaded into The Septic Guide. See how we verify licenses.