Well water testing: what to test, how often, and what it costs
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Short answer
Test your well at least once a year for total coliform bacteria, nitrate, total dissolved solids and pH, as EPA recommends. Before buying any treatment, test once more broadly: iron, manganese, hardness, hydrogen sulfide, arsenic and lead. A certified lab panel costs about $200. Many county health departments also offer low-cost bacteria and nitrate tests.
What to test, and when
| When | Test for | Why |
|---|---|---|
| Every year | Total coliform, nitrate, TDS, pH | EPA's baseline for private wells |
| Before buying treatment | Add iron, manganese, hardness, hydrogen sulfide, arsenic, lead, copper | These decide which system you need and in what order |
| Right away | Coliform and anything you suspect | After flooding, well repairs, nearby construction, or a change in taste, color or smell |
| More often | Coliform and nitrate | If infants, pregnant or nursing women, or older adults live in the home |
| If local wells have it | Uranium, radon, PFAS, pesticides | Ask your health department what's common nearby |
Where to test
| Option | Cost | Best for |
|---|---|---|
| County health department or state lab | Often low cost | Bacteria and nitrate; check what your county offers |
| Mail-in certified lab kit | About $200 for a broad well panel | A full baseline before choosing treatment |
| Home test strips | About $20–40 | Quick screening for hardness, iron and pH; not enough to choose a system |
Our pick for a full baseline
-
Best mail-in well panel: 54 analytes including bacteria
Tap Score Essential Well Water Test
You fill sample bottles at home and ship them on ice to a certified lab. Results come back as an online report with each number compared to health limits.
- 54 analytes incl. coliform and E. coli
- Heavy metals, nitrate, nitrite, hardness, pH
- Certified partner labs
- About 5 business days at the lab
About $209includes return shipping to the lab · checked October 2026 Check price at Tap Score
How to take a good sample
- Use the kit's bottles and follow its hold-time rules. Bacteria samples must reach the lab quickly, on ice.
- Sample from a cold tap that's before any treatment, or bypass existing filters, so you see raw well water.
- Remove the aerator and run the water as the instructions say before filling.
Got results? Enter them in the system matcher to see what to install and in what order.
Questions well owners ask
How much does well water testing cost?
Basic bacteria and nitrate tests through a county or state lab are often inexpensive. A broad certified mail-in panel runs about $200. A pro water treatment dealer may test for free, but expect a sales pitch.
How often should well water be tested?
At least yearly for coliform, nitrate, TDS and pH, plus any time something changes.
Can I test well water myself?
You can take the sample yourself and mail it to a certified lab. Home test strips are useful for screening, but use lab numbers to choose a treatment system.