State guide
Missouri
Missouri’s onsite wastewater program sits in the Department of Health and Senior Services (DHSS), but who issues permits depends on the county: many counties use local permitting authorities, while others are state-administered or contract counties. Missouri also keeps an official statewide list of registered onsite soil evaluators, and state law requires registration to conduct any percolation test or soil morphology evaluation used for OWTS design.
Checked against official sources on October 4, 2026. Rules and links change; confirm with the office listed before you act.
- Who regulates septic permits
- Missouri onsite wastewater is regulated by DHSS for OWTS under 3,000 gallons per day, but permit authority varies by county among DHSS, contract counties, and local authorities shown on the state authority map.
- Who can do the soil or perc test
- For design work, Missouri requires DHSS registration; registered percolation testers may test, and soil morphology evaluations may be performed by registered onsite soil evaluators, licensed professional engineers, or registered geologists meeting the rule criteria.
- Official septic permit page
- Official page →
- State fee
- $0 currently published for applications handled by DHSS because application fees were temporarily suspended effective August 28, 2026.
Official resources in Missouri
Main Missouri OWTS program page for permits, professionals, complaints, and guidance.
Official permit-process page explaining who to contact and current fee status.
State page for permit forms and payment instructions when DHSS or a contract county handles the permit.
Key facts for Missouri
- In most counties, the local health department issues OWTS construction permits.
- A construction permit is required before installing or repairing most OWTS.
- DHSS says application fees were temporarily suspended effective August 28, 2026.
- Anyone conducting a design-use percolation test or soil morphology evaluation must be registered with DHSS.
- Missouri’s onsite sewage law covers systems with flows of 3,000 gallons per day or less.
County septic and soil-evaluation offices in Missouri
| County office | city | phone | Details |
|---|---|---|---|
| Camden County Health Department - Environmental Health Services Camden | Camdenton | 573-346-5479 | County environmental page stating all permitted onsite systems require a soil test and pointing residents to the DHSS registered soil evaluator list. |
| Franklin County Building Franklin | Union | 636-583-6384 | County building page with sewer permit application links and the current county septic regulations book. |
| Lincoln County Planning and Zoning Lincoln | Not published* | 636-528-6117 | County page says to contact the Lincoln County Health Department for septic codes and permitting. |
| Lincoln County Health Department Lincoln | Troy | (636) 528-6117 | State local public health agency listing for the county office referenced for septic codes and permitting. |
| Christian County Environmental Christian | Ozark | (417) 581-7285 | County page says permits for new, repaired, or replacement onsite wastewater systems are obtained from the Christian County Health Department. |
* Not published: the official page doesn't list it. Call the office to confirm before you rely on it.
What to do next
- Check the county on the DHSS authority map first, because your permit authority may be DHSS, a contract county, or a local ordinance county.
- Hire a DHSS-registered percolation tester or onsite soil evaluator before committing to a system type.
- If DHSS or a contract county is the permit authority, request the application number before trying to pay online.
Not seeing your county office or county?
Not every county office publishes its rules online. Try these, in order:
- General Start with the statewide information above.
- Closest verified Nearest places where we have verified local data outside this state (distance from Missouri's population center, for comparison only):
- Miami County Code Services Department, Kansas · about 140 miles
- Baxter County/Mountain Home Local Health Unit, Arkansas · about 145 miles
- Boone County/Harrison Local Health Unit, Arkansas · about 158 miles
- Call to confirm Ask the official office.DHSS Onsite Wastewater Treatment
Website →Phone: (573) 751-6095 (as listed on that page, checked Oct 4, 2026)Your city or county office: Local governments →Not sure who handles it locally? USAGov's free help line, 1-844-872-4681, or the Missouri page on USA.gov can point you to the right office. - Know the current info? Tell us with a link to the official page.