Perc test pre-check by address
Before you pay $600-$1,900 for a perc test, see what the USDA soil survey already says about the lot.
Free. Uses USDA soil survey, FEMA flood maps and USGS well data. Full PDF report $19 one-time · free sample report
What is a perc test?
A percolation (perc) test measures how fast water soaks into the soil where a septic drain field would go. Test holes are dug, pre-soaked, and the drop in water level is timed (minutes per inch). Many states also require a soil profile evaluation: a licensed evaluator looks at the soil layers for signs of a seasonal high water table, bedrock or hardpan.
How much does a perc test cost?
Typical published U.S. ranges: HomeAdvisor $750-$1,900 (avg. $1,300; extremes $300-$3,000); Fixr $600-$800 (avg. $725). Counties may add a permit/application fee; engineered designs cost more.
Sources: HomeAdvisor, How Much Does a Perc Test Cost? (updated Apr 16, 2025); Fixr, Perc Test Cost (updated Jan 31, 2025)
How our pre-check relates to a perc test
| SepticSoil pre-check | Perc test / soil evaluation | |
|---|---|---|
| What it uses | Public USDA soil survey, FEMA flood map, USGS wells | Holes dug on your lot |
| Cost | Free (full PDF $19) | $600-$1,900 typical |
| Time | Seconds | Days to weeks (some states require wet-season testing) |
| Decides the permit? | No | Yes, with the health department |
The pre-check tells you whether a lot is likely to need an expensive alternative system (mound, ATU, drip) or may not be buildable at all, so you can negotiate or walk away before paying for testing.
Who to call
- Your county or local health department (environmental health / onsite wastewater program) -- they issue septic permits and tell you who may perform the test.
- A licensed soil evaluator, soil scientist, or professional engineer who designs onsite systems (titles vary by state).
- A licensed septic installer, who can often coordinate the test and the design.
Questions
What is a perc test?
A percolation (perc) test measures how fast water soaks into the soil where a septic drain field would go. A tester digs holes, pre-soaks them, and times how fast the water level drops, usually reported in minutes per inch. Many states now also require (or instead require) a soil profile evaluation, where a licensed evaluator inspects the soil layers for seasonal wetness and restrictive layers.
Sources: U.S. EPA - How Your Septic System Works; Fixr - Perc test cost (Jan 2025)
How much does a perc test cost?
Published U.S. ranges run roughly $600 to $1,900. HomeAdvisor reports most tests cost $750 to $1,900 (about $1,300 on average, with extremes of $300 to $3,000); Fixr reports $600 to $800 (about $725 on average). Price depends on the number and depth of test holes, your state's rules, and county permit fees.
Sources: HomeAdvisor - Perc test cost (Apr 2025); Fixr - Perc test cost (Jan 2025)
Is this site a perc test?
No. SepticSoil is a free pre-check from public records: the USDA soil survey's septic rating for the mapped soil at your address, FEMA's flood zone, and nearby USGS groundwater wells. It helps you decide whether a lot is worth testing. Only an on-site perc test or soil evaluation, reviewed by your county or local health department, decides what system a lot can have.
Sources: USDA NRCS - Soil Data Access; FEMA - National Flood Hazard Layer; USGS - Water Data for the Nation
Who do I call to get a perc test?
Start with your county or local health department (often the environmental health or onsite wastewater program). They issue septic permits and will tell you whether the test is done by their staff, a licensed soil evaluator, or a professional engineer. A licensed septic installer can often coordinate the test and design.
This site is not a perc test. Your county or local health department, or a licensed soil evaluator, decides what septic system a lot can have.