Septic rules and requirements in Grayson County, Texas
Septic permits in Grayson County are issued by the Grayson County OSSF Division. A new system permit costs $310. USDA rates most of the soil in the county Very limited for septic absorption fields — 92.6% of the rated acres. Grayson County OSSF Division — OSSF Permitting Requirements · checked 2026-10-05
Grayson County OSSF Division
Issues the permit
checked 2026-10-05
$310
Septic system permit
checked 2026-10-05
Very limited
USDA rating, 92.6% of rated acres
checked 2026-10-05
Who issues septic permits in Grayson County?
Grayson County OSSF Division, at 100 W. Houston, Ste. G3, Sherman, TX 75090, (903)-813-4253 or (903)-813-4247. It is part of county government. The state writes the rules it applies.
Grayson County OSSF Division — OSSF Permitting Requirements · checked 2026-10-05
What does a septic permit cost in Grayson County?
$310 for a septic system permit, on the county's own schedule.
Applies to a conventional system with a flow of 0 to 1000 gallons a day.
| Conventional System Permit | $310 | a conventional system of 0 to 1,000 gallons a day |
|---|---|---|
| Conventional System Permit | $620 | a conventional system of 1,001 to 2,000 gallons a day |
| Conventional System Permit | $930 | a conventional system of 2,001 to 3,000 gallons a day |
| Conventional System Permit | $1,240 | a conventional system of 3,001 to 4,000 gallons a day |
| Conventional System Permit | $1,550 | a conventional system of 4,001 to 5,000 gallons a day |
| Aerobic System Permit | $20 | a aerobic system the source lists as Add $20 to Conventional System Permit |
| Repair Permit | $100 | a repair system |
| Paper Application Processing Fee | $50 | a system the source lists as Add $50 |
| Reinspection Fee | $100 | any system |
| Contract Renewal | $20 | any system |
| Contract Renewal Late Fee | $125 | a system the source lists as Add $125 |
A system with a maintenance contract pays an extra fee.
Grayson County Development Services Fees (revised 04/14/2026) · checked 2026-10-05
How long does approval take in Grayson County?
7 days.
Applies to the permit process, which takes five to seven days.
Grayson County OSSF Division — OSSF Permitting Requirements · checked 2026-10-05
Is the soil in Grayson County suitable for a septic system?
USDA rates most of the county Very limited for septic absorption fields — 92.6% 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 2026-10-05
What Grayson County sets itself
The state writes the code. Grayson County adds the rules below. They are what makes this page differ from the Texas requirements.
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1.5 acres
Applies to a lot with no public water and no drip irrigation system.
The state sets no such lot size, so this rule is the county's own.
Order Adopting Rules of Grayson County, Texas for On-Site Sewage Facilities, Section 10(E)(1)(a) · checked 2026-10-05
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The lot must use an aerobic system.
Applies to a lot under 2.5 acres.
The county sets this rule on top of the state rules.
Order Adopting Rules of Grayson County, Texas for On-Site Sewage Facilities, Section 10(D) · checked 2026-10-05
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A lot within 100 feet of a public sewer must connect to it.
Applies to a lot within 100 feet of a public sewer.
The County Engineer may approve a waiver in writing.
Order Adopting Rules of Grayson County, Texas for On-Site Sewage Facilities, Section 10(C) · checked 2026-10-05
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Every RV must use an aerobic system.
Applies to a lot with four or more RVs.
Order Adopting Rules of Grayson County, Texas for On-Site Sewage Facilities, Section 10(G) · checked 2026-10-05
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.
- Grayson County OSSF Division — OSSF Permitting Requirements
- Grayson County Development Services
- Order Adopting Rules of Grayson County, Texas for On-Site Sewage Facilities, Section 10(E)(1)(a)
- Grayson County Development Services Fees (revised 04/14/2026)
- Grayson County — MyPermitNow Navigation Guide
- 30 TAC §285.91(2), Table II -- Septic Tank and Aerobic Treatment Unit Sizing
- USDA NRCS Soil Data Access (SSURGO)
Verify before you act. Septic rules are set locally and they change. Check anything here before you spend money on it. Call the Grayson County OSSF Division, on (903)-813-4253 or (903)-813-4247.