Water Filtration & Treatment in Armonk & North Castle, NY

Armonk (Town of North Castle) skews newer than the coastal villages: the typical home was built around 1989, though 43% still pre-date 1980. On large wooded lots, drainage and grading often matter more than the basement wall itself. Public water suppliers in Westchester test and report on their water, while private well owners are responsible for their own. The county health department says private wells must be tested when a property is sold or leased and before use of a new well, and recommends periodic testing otherwise. Water treatment itself is not a county-licensed trade, but connecting plumbing generally requires a licensed plumber, so ask who does that work and for the license number.

Water filtration companies for Armonk & North Castle

How we pick: we list up to six companies per page. Independent firms come first, then firms based outside Westchester, then franchise or network affiliates. Companies that name the town as served come before those that serve the whole county. Listings are free, not paid, and not an endorsement. Home improvement license status was looked up in the Westchester County consumer license search on Oct 26 to 27, 2026, plumber license status in the county trade license search on Oct 27, 2026, and NYS mold license status in the state Labor Department data set; each profile shows what we found.

Housing in Armonk & North Castle

PlaceTypical year builtBuilt before 1950Built before 1980Median home value
Armonk198913.6%43.2%$1,073,300

Source: U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates (tables B25035, B25034, B25077), retrieved Oct 2026. Estimates carry a margin of error.

What it costs

We did not find a published Westchester-specific price list, so these are national HomeGuide ranges: $850 to $5,400 installed for a whole-house filtration system, $800 to $4,000 for a well-water filtration system, and $1,200 to $3,800 for a salt-based water softener with installation. Water testing is $100 to $300. Your final price depends on what your water test finds. Full cost guide with sources.

Frequently asked questions

How many water filtration companies serve Armonk & North Castle?

We show 6 of 6 companies we found for Armonk & North Castle: 1 name Armonk & North Castle as an area they serve, and the rest serve all of Westchester County. Always confirm a company covers your address.

Who handles the plumbing for water treatment in Armonk & North Castle?

Plumbers are licensed through the county's separate trade license search. Ask each company who does the plumbing connections, ask for the license number, and look it up.

Do I need a filter or softener?

Test first. The CDC says no single treatment removes every problem, so check that a system removes the specific germ or chemical your test found. HomeGuide notes that softeners treat hardness but do not filter water.

How often should a private well be tested?

The Westchester County Health Department says EPA recommends testing private water supplies annually for nitrate and coliform bacteria, or more often if you suspect a problem.

Nearby

Sources

  1. U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, tables B25034, B25035, B25077 (via Census Reporter)

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