Which water test kit should you buy?
For drinking water decisions, choose a kit that mails samples to a certified lab, not a strip you read at home. For a well, make sure it includes bacteria and nitrate. Lab-backed mail-in kits run about $189 to $1,125 at Tap Score depending on coverage, and a state lab's line-item tests start around $35.
Prefer a local lab? Certified labs near you
Strips vs certified lab kits
| Test strips and home kits | Certified lab kits | |
|---|---|---|
| What you get | A color you match to a chart | A lab report with measured numbers |
| Good for | Hardness, chlorine, rough pH | Bacteria, nitrate, metals, PFAS, anything health-related |
| Accepted for a home sale | No | Often, if collected properly |
| Typical cost | Low | About $35 per test at a state lab to $1,125 for a full mail-in panel12 |
For deciding whether to drink the water or what treatment to buy, only a certified lab result is worth acting on.
What a good mail-in kit includes
- A certified lab. Look for state certification or accreditation for the tests you're buying.
- The EPA's yearly basics for wells: total coliform bacteria, nitrate, total dissolved solids and pH.3
- Clear hold-time instructions for bacteria, plus prepaid overnight shipping if bacteria is included.
- A report that compares results to EPA limits, with next steps.
Compare prices
Tap Score's well kits cost $209, $399 and $1,125 as of October 2026, and its city water kits $189, $299 and $815.2 For just a few tests, a state or local certified lab is usually cheaper: Wisconsin's state lab charges $35 each for bacteria and nitrate.1
How we choose products
We haven't hands-on tested water kits side by side yet, so this page explains how to choose rather than ranking brands. When we recommend specific kits, we'll explain how we tested them, and any link that earns us a commission will be labeled.
Prefer a local lab? Certified labs near you
Show all 40
Bad result? Get help from water treatment pros near your area
Tell us what your test found and we'll connect you with up to three local water treatment companies.
What happens next
- We match your ZIP to water treatment companies nearby.
- They contact you directly to talk through your results.
- Compare options and pick one, or none. No fee, no obligation.
Free, no obligation. We don't sell your details to anyone else.
Just need a lab? Every certified lab is listed above with directions.
Common questions
Are home water test strips accurate?
They can flag big problems with hardness, chlorine or pH, but they aren't precise and can't reliably detect bacteria, arsenic or lead at health-limit levels. Use a certified lab for anything that affects whether you drink the water.
Is a mail-in kit as good as a local lab?
If the lab analyzing it is certified for the tests, yes. The main risk is time: bacteria samples have short hold times, so ship them the way the kit says.
Can I use a mail-in kit for a home sale?
Check with your lender first. Many want a sample collected by the lab, its approved sampler, or an inspector.
What should a well water kit include?
At minimum total coliform bacteria, nitrate, and pH. Total dissolved solids rounds out the EPA's yearly list. Add local concerns like arsenic, uranium, manganese or PFAS.
Sources
- Public environmental and water testing prices (effective July 1, 2026) Wisconsin State Laboratory of Hygiene
- Tap Score water testing (prices as of October 2026) SimpleLab Tap Score
- Protect Your Home's Water US EPA