Notes for people on private wells

If your home gets water from a private well, nobody tests it for you. U.S. EPA rules that protect public water systems don't apply to private wells, so testing is up to the owner.^CDC

This site collects the boring but useful details in one place: what to test for, how to read the numbers on a lab report, which rules apply in your state, and who to call locally. We take each fact from a government or university source, link to it, and date the page so you can see when we last checked it.

Browse by state

Each state page covers who's on wells, the home-sale testing or disclosure rule, regional contaminants, certified-lab lookups, free or low-cost testing, well-log databases and local contacts.

• FloridaFlorida has no well test requirement at sale. County health department testing, what to test, free sampling near contamination, NELAP-certified labs, well completion reports by water management district, and contacts, with sources.State overview
• GeorgiaGeorgia's well water testing advice, UGA's home loan closing test, uranium and radon in the Piedmont, arsenic in the Coastal Plain, setback distances, certified labs and contacts, with sources.State overview
• IndianaIndiana's seller disclosure for wells, glacial arsenic data, Indiana Department of Health lab fees, certified labs, the IDNR water well record database, and county contacts, with sources.1 county page
• MichiganMichigan private well facts in one place, covering new-well testing rules, the MDHHS testing schedule, arsenic in southeast Michigan, testing options, and our Michigan county pages.3 county pages
• MinnesotaMinnesota's well disclosure law for home sales, MDH testing advice, arsenic in new wells, free nitrate clinics, accredited lab search, the Minnesota Well Index, and county contacts, with sources.1 county page
• New HampshireNew Hampshire private well facts in one place, covering arsenic, radon and PFAS, NHDES testing guidance, town testing rules, accredited labs, and our New Hampshire county pages.2 county pages
• New YorkNew York's property disclosure questions on wells, county and town testing laws at sale, NYSDOH testing advice, ELAP lab search, free PFAS testing, DEC well records, and contacts, with sources.1 county page
• OhioOhio's home-sale disclosure, county point-of-sale well inspections such as Summit County's, arsenic estimates, what to test, Ohio EPA certified labs, the ODNR well log search, and contacts, with sources.1 county page
• PennsylvaniaPennsylvania private well facts in one place. There are no statewide testing rules, so this covers DEP's testing advice, Penn State county data, where to buy bacteria test kits, and our Pennsylvania county pages.4 county pages
• VirginiaWhat Virginia requires when a home with a well is sold, what VDH says homebuyers should test for, the Virginia Household Water Quality Program clinics, certified lab search, well records and contacts, with sources.State overview
• WisconsinWhat Wisconsin requires (and doesn't) when a home with a well is sold, the DNR inspection form, statewide test data, certified lab lists, well records, the Well Compensation Grant, and contacts, with sources.1 county page

County pages only (state overview coming): Maine, New Jersey, North Carolina.

Start here: guides

• Buying a home with a well: inspection contingency, water tests, and which states require testing at saleWhat to put in your offer, which water tests to order by region, flow and yield tests, septic distances, well logs, sourced costs, seller questions, red flags, and a state-by-state table of home-sale well testing rules. Printable checklist included.Last checked 2026-10-22
• How to read your well water test resultsWhat iron, manganese, hardness, sulfur (H2S), pH, nitrate, coliform/E. coli, and arsenic numbers mean, compared with EPA and state limits, with sources.Last checked 2026-10-21
• Arsenic in well water: the best way to test, and treatment optionsHow to test a private well for arsenic, what the 10 µg/L and 5 µg/L numbers mean, and which treatment types state agencies say work (and don't), with sources.Last checked 2026-10-21
• Iron in well water: what to test, and what to buyHow to figure out what kind of iron problem you have, and which treatment Penn State Extension and Maine CDC match to each iron level, from softeners to greensand to chlorination with filtration. With sources.Last checked 2026-10-21
• Whole-house vs. point-of-use filters for well water: which problems need whichWhen a well problem needs whole-house (point-of-entry) treatment and when a single-tap (point-of-use) unit is enough, based on what state agencies say about each contaminant. With sources.Last checked 2026-10-21
• Best way to test well water: state lab, county health department, certified lab, or mail-in kitThe main ways to get a private well tested, what a full panel should include, how to take a sample so the result means something, and what to do with the report. With sources.Last checked 2026-10-21
• Nitrate in well water: testing, infants, and treatment optionsWhy nitrate matters most for babies, which wells are most at risk, why boiling makes it worse, and the treatment types state agencies list. With sources.Last checked 2026-10-21
• How often to test a private well: CDC and state schedules side by sideYearly, every 3–5 years, or just once. A side-by-side comparison of what CDC and the health and environment agencies in NH, ME, MI, PA, NJ and Union County, NC recommend, plus the events that should prompt a test. With sources.Last checked 2026-10-21
• Uranium and radon in well water: testing and treatmentWhat the uranium, gross alpha and radium standards are, why radon in well water is mostly an air problem, how common radon is in New Hampshire wells, and the treatment types Maine CDC lists. With sources.Last checked 2026-10-21
• Shock chlorinating a well: when it helps, how it's done, and retestingWhen agencies recommend shock chlorination, how often it actually clears bacteria, key safety points from state and county procedures, and the retest schedule. With sources.Last checked 2026-10-21
• How much does well water testing cost? State lab fees vs. university and private labsPublished, dated fees from state and university labs (Indiana, Florida, South Carolina, Penn State), what each test covers, and where to look up your own state's options. With sources.Last checked 2026-10-21
• Well flooded? Inspecting, disinfecting, and retesting a private well after a floodWhat EPA, CDC and the Minnesota Department of Health say to do when flood water reaches a private well, from electrical safety and inspection to disinfection and the bacteria retest schedule. With sources.Last checked 2026-10-21

County pages

Each county page lists the local health department contact, the state's private-well rules, and where to find a certified lab, with sources and a "last checked" date.

See all counties →

How this site works

• Sources first. Every limit, rule, price, and phone number links to the agency or lab that published it. If we can't verify something, we leave it out.
• Dated pages. Rules and prices change. Each page shows when we last checked it.
• No product pitches dressed up as advice. We may add affiliate links later, and if we do, we'll say so on the page. See our affiliate disclosure.