Well Water Testing in New Hampshire: A Buyer's Guide (2026)

Quick answer: New Hampshire does not legally require well water testing to buy a home, but you should always do it — and most lenders will insist. Roughly 40% of NH homes draw from a private well, and the state sits on arsenic- and radon-rich bedrock. A standard NHDES test panel (arsenic, bacteria, lead, uranium, nitrate, radon and more) runs about $85–$130 and is the single cheapest form of protection you can buy before closing.

If you're shopping for a home in southern New Hampshire, there's a good chance the water comes from a well in the backyard rather than a municipal main. That's not a problem — hundreds of thousands of Granite Staters drink excellent well water every day — but it does mean the quality of your water is your responsibility, not the town's. This guide walks through exactly what well water testing in New Hampshire should cover, what it costs, and what to do when a result comes back high.

Does New Hampshire require well water testing to buy a home?

No. There is no state law forcing a buyer or seller to test a private well before a sale closes. But that's misleading, because in practice the test happens anyway. Since 2025, New Hampshire sellers must disclose known risks of arsenic, radon, lead and PFAS in a private well, which pushes the topic onto the table in almost every transaction. And if you're financing with an FHA or VA loan — or many conventional loans on well-served homes — your lender will require a passing water test as a condition of the mortgage. Skipping well water testing in New Hampshire is one of the few corners in a home purchase we'll always tell a client not to cut.

What should a New Hampshire well water test include?

The New Hampshire Department of Environmental Services (NHDES) recommends a "Standard Analysis" panel for anyone buying a home on a private well. A proper panel covers arsenic, coliform bacteria, lead, uranium, nitrate and nitrite, fluoride, chloride, copper, hardness, iron, manganese, sodium and pH. For the drilled bedrock wells that are common across Bedford, Amherst and Hollis, add radon and a gross alpha screen. Testing well water before buying with anything less than the full Standard Analysis leaves real hazards invisible — arsenic and radon have no taste, color or smell.

Why do arsenic and radon matter so much in New Hampshire?

Because the ground here is unusually generous with both. New Hampshire's fractured granite bedrock leaches naturally occurring arsenic into groundwater: roughly one in three private wells contains detectable arsenic, and an estimated 30% of bedrock wells exceed the state's health limit. New Hampshire lowered that arsenic standard from 10 parts per billion to 5 ppb (effective July 2021) precisely because long-term exposure is linked to cancer and cardiovascular disease. Radon is even more widespread — NHDES estimates that most private wells in the state exceed the suggested action level. Two neighboring wells on the same street can test completely differently, which is why a private well water test in NH is specific to your address, not the neighborhood.

How much does well water testing cost in New Hampshire?

Far less than the problems it catches. A standard NHDES-style analysis through the state Public Health Laboratory or a NHELAP-accredited private lab typically runs about $85 to $130, with basic bacteria-and-nitrate panels available for less and specialized arsenic-species or PFAS testing available on top. Budgeting for well water testing in New Hampshire is easy: against a single-family median sale price near $575,000 (NHAR, mid-2026), a $100 water test is a rounding error — and if it turns up arsenic, it can save you from a five-figure surprise or hand you real leverage in negotiations.

What happens if the results come back high?

A bad result is not a dealbreaker — it's information. Most common problems are treatable: arsenic and uranium respond to point-of-entry treatment systems, radon is stripped with an aeration unit, and bacteria issues are often resolved by shocking and re-testing the well. Systems typically run from a few hundred dollars for a filter to a few thousand for whole-house treatment. In our experience, the smartest move is to get the test done early in the inspection period so you have room to ask the seller for a credit, a price reduction, or installation of treatment before closing. That's a conversation The Phinney Team has with buyers across Bedford, Manchester and Nashua constantly — and it almost always ends well when the test is done on time.

Related reading

If you're weighing your options as a buyer, our guide on whether you need a real estate agent to buy a home in NH is a useful companion. And once you're thinking about carrying costs, see our breakdown of Bedford NH property taxes so nothing at the closing table surprises you.

Frequently asked questions

How often should I re-test my well after I buy?

NHDES recommends re-testing the Standard Analysis panel every three to five years, and testing for bacteria annually. Re-test sooner if you notice a change in taste, color or odor, or after any work on the well or septic system.

Can I use a store-bought test strip instead?

No. Home test strips can't reliably detect arsenic, radon or uranium at the low, dangerous concentrations that matter in New Hampshire. Use a NHELAP-accredited laboratory so the results hold up with your lender and are legally meaningful.

Who pays for well water testing, the buyer or the seller?

It's negotiable. Buyers most often pay for their own inspection-period testing, but when a lender requires a passing test, sellers frequently cover it or share the cost. Your agent should build the expectation into the offer.

Does a failed water test kill the deal?

Rarely. Because most contaminants are treatable, a high result usually becomes a negotiation over who installs and pays for treatment — not a reason to walk. Testing early in the contingency period keeps every option open.

What about PFAS in New Hampshire well water?

PFAS ("forever chemicals") became a mandatory NH seller disclosure item in 2025. It isn't part of the basic Standard Analysis, so ask your lab to add a PFAS panel if the home is near a known source or you simply want peace of mind.

Buying a home on a private well in southern New Hampshire? Start with our buyer resources, explore listings in Bedford and Manchester, or reach The Phinney Team at teamphinney.com to make sure your water test happens on time and works in your favor. Authoritative guidance is available from NHDES Private Wells and Dartmouth's Toxic Metals research program.