If you want to test my well water answered properly, start with the two tests every private well needs: a bacteria test and a general chemistry panel covering hardness, iron, manganese, pH, nitrate and total dissolved solids. Everything else on the menu is chosen from what your neighbors, your geology and your symptoms suggest, not from a catalog.
Nobody tests your well but you
A city utility is required to sample its own supply and report the results. A private well is not: the EPA states plainly that private wells are not federally regulated under the Safe Drinking Water Act, and that around 15 percent of the US population, over 43 million people in more than 23 million households, drink from one. That is the whole reason this question comes up. The well owner is the water quality department, and the only data that exists is data you pay to create.
The panel worth paying for
Ask the lab for coliform and E. coli, nitrate and nitrite, pH, hardness, iron, manganese, sulfate, chloride and total dissolved solids. Add arsenic, uranium, radon or fluoride if your state geology is known for them, and lead if the house has older plumbing or a brass well pitless adapter. If a nearby gas station, farm field, orchard or landfill sits upgradient, name it when you call the lab so they suggest the right add-on. A USGS study of 2,100 private wells found about one in five carried at least one contaminant above a human-health benchmark, so a clean-looking, clear-tasting well is not evidence of anything.
Where to send it
Use a state-certified drinking water laboratory. Your county health department keeps a list, and many run low-cost bacteria testing themselves. The lab supplies sterile bottles with preservative already inside, which is why you cannot use a jam jar: the bottle chemistry is part of the test. Some analytes have short hold times, so labs will tell you to sample on a weekday morning and deliver the cooler the same day. If you are shopping for a nearby service rather than mailing a kit, our well water testing guide covers what a local tester should be doing on site.
Collecting a sample that means something
Pick an indoor cold tap closest to the pressure tank, take off any aerator or attached filter, and let the line run until the water turns cold and steady. For bacteria, disinfect the spout, wash your hands, run a gentle stream, and fill the bottle without touching the rim or the inside of the cap. Do not rinse a bottle that came with preservative in it. Fill to the line, cap it, chill it, and log the date, the tap you used and how long you flushed, because a lab result with no sampling notes cannot be interpreted later.
Reading the result before you buy anything
Results only mean something against the symptom you started with. Bacteria present means disinfection and a look at the well cap, casing and grouting before any filter is considered. High hardness with clear water points at a softener. Iron and manganese point at oxidation and filtration, and the treatment differs depending on whether the metal is dissolved or already rust-colored in the glass. Nitrate points at surface influence and usually at reverse osmosis for drinking water. Buy the equipment that matches the number, and retest after installation to prove it worked.
Questions people ask about test my well water
How often should I test a private well?
Test for bacteria and nitrate every year, run a fuller chemistry panel every few years, and retest immediately after flooding, well work, a new pump, or any change in taste, smell or color.
Can I test my well water myself with a kit?
Home kits are useful for hardness, chlorine, pH and a rough iron reading, and some include a bacteria vial. For anything with a health limit, such as nitrate, arsenic or lead, use a certified laboratory instead.
Should I sample before or after my existing filter?
Both, if you can. A raw sample taken before treatment tells you what the well delivers, and a treated sample proves whether the equipment you already own is still doing its job.
Does a clear, good-tasting well need testing?
Yes. Bacteria, nitrate, arsenic and lead are invisible and tasteless at levels that matter, so appearance and taste tell you nothing useful about safety.