Testing
How to test your tap water for lead
Use a state-certified laboratory and follow its sampling instructions exactly, usually a first-draw sample after water has sat in the pipes. Compare your result with EPA's lead action level, but remember that EPA says there is no known safe level of lead exposure.
Why test
EPA says lead cannot be seen, tasted or smelled in water, and that “testing is the only sure way of telling whether there are harmful quantities of lead in your drinking water”. Lead in your water depends on your own plumbing and service line, so your utility’s result cannot stand in for it (where lead comes from).
Step 1: Ask your utility first
Many utilities test for lead on request, sometimes free. They may also know whether your service line is lead. EPA suggests contacting your water supplier for testing information and for whether the service connector in your home or area is made of lead.
Step 2: Choose a certified lab
EPA says a list of certified laboratories is available from your state or local drinking water authority, and EPA publishes state certification program contacts. The lab should be certified for drinking water analysis. Mail-in services sell kits and use certified labs; confirm that is true of the one you pick (kits compared). EPA WaterSense mentions home test kits as a way to check that a treatment system is working; for a lead result you can rely on, use a certified lab.
Step 3: Collect the sample the way the lab says
Instructions differ, so follow your lab’s. For a first-draw sample the usual approach is to avoid using water for several hours and then collect from the cold tap before running anything. If the lab wants a flushed sample too, they will tell you. Do not improvise, because the sample timing determines what the result means.
Step 4: Read the result
Results come in micrograms per liter (µg/L), the same as parts per billion (ppb).
- EPA’s current lead action level is 15 ppb. The Lead and Copper Rule Improvements lower it to 10 ppb, with compliance dates beginning November 1, 2027 (details).
- The action level is a regulatory trigger for utilities, not a health threshold. EPA sets the health goal at zero.
- A result of “not detected” depends on the lab’s reporting limit. Ask what it is.
If the result is high
Follow EPA’s steps: flush, use cold water, clean the aerator, and use a filter certified for lead (guide). Tell your utility, consider replacing lead fittings, and ask a clinician about testing children. Retest after changes to confirm they worked.
Sources
Not medical or legal advice. This guide summarizes public documents so you can ask better questions of your utility, your health department or a certified lab. For health concerns, talk to a clinician; for compliance questions, to your state drinking water program. Pages on this site that name products may earn a commission, as disclosed on the affiliate disclosure page.