Find out where to test your well water, county by county
Most lab finders only list labs by state. We go county by county: which certified labs serve your county and take mail-in samples, free or subsidized health department and extension programs, what's actually turning up in local wells, what testing costs, and how to collect a sample. Every fact is sourced and dated.
County guides
- Rockingham County, New Hampshire
Arsenic and radon are the big issues: in state lab data, 31% of Rockingham County wells tested were over 5 µg/L arsenic and 32% over the 2,000 pCi/L radon advis...
Last verified 2026-10-25 - Wake County, North Carolina
Wake County runs its own well water testing program (packages from $140-$175 plus a $50 trip fee, with income-based pricing of $73 or $182.50). Eastern Wake Cou...
Last verified 2026-10-25 - Chester County, Pennsylvania
The Chester County Health Department no longer tests well water; it keeps a list of labs instead. Penn State's mail-in lab charges $60-$220 per package, and its...
Last verified 2026-10-25
No county guide yet. More are added regularly. Try your state page or the testing guide.
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Guides
How to test your well water
Pick a lab, collect a clean sample, and get it to the lab in time.
What to test for
Bacteria, nitrate, arsenic, radon, uranium, lead, PFAS: what to test and how often.