Home water testing: when, why, and which kit
Most homeowners have never tested their water. They rely on utility Consumer Confidence Reports for city water, or assume their well is fine because it always has been. Testing closes the gap between what the utility monitors at the treatment plant and what arrives at your kitchen faucet — which can be meaningfully different, particularly in older homes and on private wells.
When to test
Annually, for all private well households. The EPA recommends annual testing for bacterial contamination and nitrates for all households on private wells. Wells are not tested by any regulatory body — you are the monitoring system for your own water supply. Annual bacterial and nitrate testing costs $30 to $60 and is the minimum responsible practice for well owners.
After any well work. Any time a well contractor opens the casing — pump replacement, well deepening, pressure tank replacement — retest for bacterial contamination before returning to normal use. Construction activity can introduce surface bacteria into the casing.
After a boil water advisory is lifted. Once the advisory is lifted and you have flushed the household plumbing, consider testing to confirm your tap water is clear. Your utility's tests confirm the distribution system; they do not test the water at your specific faucet after flushing.
When buying or renting a home. Particularly in homes built before 1986, lead pipe and lead solder in interior plumbing are a meaningful concern. Utility water can be lead-free at the main; interior plumbing can still leach lead at the tap. Test before moving in, not after six months of residence.
If you notice changes in taste, odor, or appearance. A sudden change in water character — cloudiness, off-smell, discoloration — warrants immediate testing rather than waiting for the next scheduled test.
The three tiers of home water testing
Tier 1: Home test strips — $10 to $25
Basic orientationDip strips that change color in response to specific parameters — pH, chlorine, hardness, nitrates, iron, and sometimes lead. Results in 30 seconds. Useful for a quick orientation to your water chemistry and for monitoring known parameters over time. Not sensitive enough for regulatory thresholds or health-relevant PFAS concentrations. The right starting point before committing to a lab kit, not a substitute for one.
Tier 2: Mail-in lab kits — $50 to $200
Actionable dataYou collect a water sample at your tap, mail it to an accredited laboratory, and receive results in five to ten business days. This is where real data comes from. Lab kits cover lead, copper, bacteria (total coliform, E. coli), nitrates and nitrites, hardness, pH, turbidity, and additional parameters depending on the panel. Results arrive benchmarked against EPA standards and often include plain-language interpretation. Tap Score by SimpleLab and SimpleLab's own branded kits are the two most widely available options with the clearest result formats.
Tier 3: PFAS-specific panels — $200 to $300
Full chemical pictureA specialized subset of lab testing using EPA Methods 537.1 and 533, which detect PFAS compounds at parts-per-trillion concentrations. This is the only testing method that reliably identifies PFAS at health-relevant levels. Tap Score's PFAS panel (~$249) covers the full range of regulated and commonly detected PFAS compounds. Results arrive with concentration data benchmarked against EPA MCLs and independent health guidance values. Warranted for any household with reason to believe PFAS may be present — near military installations, airports, industrial sites, or in any of the 3,539 systems where UCMR 5 found detectable PFAS.
City water vs well water testing priorities
City water households should focus on what the utility does not test: lead at the tap (interior plumbing leaches lead regardless of whether utility water is lead-free), and PFAS if your utility's UCMR 5 data or Consumer Confidence Report shows detectable levels. A city water household that has tested for both and found neither has established a meaningful baseline.
Well water households need the broader panel: annual bacterial testing and nitrates as a minimum, with periodic comprehensive testing (every three to five years) that includes heavy metals, hardness, pH, arsenic, manganese, and radon depending on regional geology. Well water chemistry is location-specific in ways city water is not — local geology determines what is naturally present, and that varies considerably even within a county.
What to do right now
- 1 Read your Consumer Confidence Report if you are on city water. Find your utility online, download the most recent CCR, and check for lead action level exceedances and PFAS monitoring results. This is the starting point before buying any test kit.
- 2 If you are on a private well and have not tested in over a year, order a basic well water kit now. A Tier 2 lab kit covering bacteria, nitrates, lead, and pH runs $50 to $80 and is the minimum responsible annual practice.
- 3 Order a PFAS panel if your CCR shows detectable PFAS or if you live near a military installation, airport, or industrial site. The $200 to $250 cost is the most direct way to know your actual exposure level rather than estimating from utility-level data.
- 4 Test before buying a filter system, not after. A test result tells you what to filter — which determines which filter to buy. Buying a filter first and testing second is a common sequence that often leads to a filter that does not match the household's actual needs.
On the shelf
Tap Score by SimpleLab
The clearest result format in the mail-in lab kit category. City water kits from $39; well water kits from $79; PFAS panel ~$249. Results arrive benchmarked against EPA standards with plain-language interpretation. Tested at EPA-accredited laboratories.
Full water test kit comparison →Go deeper
Full guidance on NWS:
Related field notes
Sources
- EPA: Private Wells — Protect Your Home's Water
- CDC: Private Well Testing
- NSF International: Accredited laboratory directory