Septic rules and requirements in Montgomery County, Texas
Septic permits in Montgomery County are issued by the county environmental health office. A new system permit costs $295. USDA rates most of the soil in the county Very limited for septic absorption fields — 95.3% of the rated acres. Montgomery County Environmental Health Services — How to Obtain a Permit to Construct a Septic System · checked 2026-09-23
$295
Septic system permit
checked 2026-09-23
Very limited
USDA rating, 95.3% of rated acres
checked 2026-09-22
What does a septic permit cost in Montgomery County?
$295 for a septic system permit, on the county's own schedule.
Applies to a new residential septic system. It includes the fee the county collects for the Texas Commission on Environmental Quality.
| New System - Residential (construct a new septic system) | $295 | a home with a system |
|---|---|---|
| New System - Commercial (construct a new septic system) | $345 | a business with a system |
| Add-on Modification - Licensed (addition to septic system with an existing license on file for individual purposes) | $145 | a system the source lists as addition to a septic system with an existing license on file for individual purposes |
A commercial system costs more. An add-on to an existing system costs less, and so does a subdivision review or a floodplain variance. A failed inspection carries its own fee.
Montgomery County Environmental Health Services — How to Obtain a Permit to Construct a Septic System · checked 2026-09-23
Is the soil in Montgomery County suitable for a septic system?
USDA rates most of the county Very limited for septic absorption fields — 95.3% of the rated acres. A rating describes the ground, not a parcel. The county's site evaluation decides each lot.
USDA NRCS Soil Data Access (SSURGO) · checked 2026-09-22
What Montgomery County sets itself
The state writes the code. Montgomery County adds the rules below. They are what makes this page differ from the Texas requirements.
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$295
Applies to a new residential septic system. It includes the fee the county collects for the Texas Commission on Environmental Quality.
A commercial system costs more. An add-on to an existing system costs less, and so does a subdivision review or a floodplain variance. A failed inspection carries its own fee.
Montgomery County Environmental Health Services — How to Obtain a Permit to Construct a Septic System · checked 2026-09-23
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No septic permit will issue for a site inside the floodway.
Applies to a new system on a tract inside the floodway.
State rules let an engineer design a system for a floodway site instead. The county allows no floodway system, engineered or not.
Montgomery County Environmental Health Services — How to Obtain a Permit to Construct a Septic System · checked 2026-09-23
Sources
Each figure above has a government source and a checked-on date. USDA's Soil Data Access service supplies the soil records. A script writes them, and nobody types them.
Verify before you act. Septic rules are set locally and they change. Check anything here before you spend money on it. Call the county environmental health office.