About this list
- Agency
- Connecticut Department of Public Health - Environmental Laboratory Certification Program
- Format
- PDF table (+ commercial-lab PDF for addresses)
- Homeowner flag
- Explicit 'Private Well Testing' column.
CT DPH In-State Approved Commercial Laboratories Certified to Test Drinking Water. Fetched 2026-10-29 (UTC).
Official sourceTesting your well in Connecticut
How often to test
- Connecticut's health department guidance, as summarized by the state legislature's research office in 2019: basic indicators every year; lead at least once; arsenic, uranium and radon at least once and ideally every five years; VOCs at least once. [1]
Free testing
We found no statewide free testing program in Connecticut. Ask your county health department whether it runs one.
Buying or selling a home
- Before a property with a private well is sold or rented, state law requires that the buyer or tenant be told the Department of Public Health's well-testing material is available and be given a copy; that material recommends testing. [2]
State lab and rules
- New wells: since October 1, 2022, the owner of every newly built private well must have it tested by a laboratory, including coliform, nitrate, nitrite, sodium, chloride, iron, manganese, hardness, turbidity, pH, sulfate, color, odor, arsenic and uranium (plus a first-draw lead sample if the well serves an existing building), and send the results to the local health authority. A new well may not be used for household purposes until the local health authority finds the results meet the state limits. [2]
- The local director of health may require testing for arsenic, radium, uranium, radon or gross alpha where there are reasonable grounds to suspect them, such as known local geology. [2]
Show the numbers
| Item | Value | Note |
|---|---|---|
| Zone 1 | 4 historic counties | |
| Zone 2 | 3 historic counties | |
| Zone 3 | 1 historic counties |
Radon in indoor air, not in water. EPA: Zone 1 = highest potential (average indoor radon may be above 4 pCi/L); Zone 2 = 2 to 4; Zone 3 = below 2. EPA says the map should not be used to decide whether an individual home needs testing. Source: U.S. EPA, Map of Radon Zones, county list (EPA 402/A-16/001, spreadsheet Sep 2025), accessed 2026-11-01.
- Connecticut General Assembly OLR Research Report 2019-R-0246, Private well testing (Oct 16, 2019)
- Connecticut General Statutes ยง 19a-37 (current, chapter 368a)
- U.S. EPA, Map of Radon Zones, county list (EPA 402/A-16/001, spreadsheet Sep 2025)
Loan test (FHA, VA, USDA) in Connecticut
- VA. Test results are valid for 90 days from the date the local health authority certifies them, unless the local authority says otherwise. VA’s chapter names no list of contaminants: the water must meet the local health authority’s requirements, or EPA guidelines where it has none. Your lender may ask for specific tests.
- FHA. A well test is required in the situations FHA’s handbook lists, among others, and the report may not be more than 180 days old at disbursement.
- USDA. Guaranteed loans need a water quality test for a private well, done by the local health authority or a state-certified lab, and no more than 180 days old at closing.
Lenders can ask for more (extra tests, a particular lab, who takes the sample): ask your lender before you book. Federal rules as read on Nov 3, 2026 source 1 source 2 source 3. Full comparison: VA, FHA and USDA well water test requirements. Loan test kits sold by mail, with price and days to results: kits compared.
What Connecticut labs say on their own websites
State lists say what a lab is certified for, not whether it takes your sample or what it costs. We read each lab’s own site; a second reader re-checked every fact below. 1 labs on this list are on our register so far; 1 say they take homeowner samples and 0 print a price.
Say they take homeowner samples: ALS Environmental - Stratford.
Prices exactly as each lab prints them, read 15 Nov 2026; re-checked every 90 days. Labs not shown have not been read yet or print nothing for homeowners. Confirm price and turnaround with the lab.
Labs by contaminant
Labs on the Connecticut list for one test, with homeowner-accepting labs first.
Well water by county
Private-well population (USGS, 2015), arsenic estimate, radon zone and nearby labs for each county with at least 1,000 people on private wells, largest first.