Well Water Nerd

Well water testing in Montana

Nobody tests a private well unless the owner does. In Montana, the public record says to start with nitrate, arsenic, uranium, then bacteria every year. Below: what to order, where, what it costs, and the county-by-county results that set the order.

What to test for first

  1. 1
    Nitrate
    11% of 8,286 local samples were above the limit.
  2. 2
    Arsenic
    10% of 5,666 local samples were above the limit.
  3. 3
    Uranium
    9% of 530 local samples were above the limit.
  4. 4
    Radium (226 + 228)
    5% of 1,885 local samples were above the limit.
  5. 5
    Lead
    4% of 6,939 local samples were above the limit.

Test your Montana well for nitrate, arsenic and uranium

Certified lab analysis of your own tap water, bottles and prepaid return shipping included. The Essential well panel covers arsenic, uranium, nitrate, lead, copper, manganese, iron, sodium and bacteria; radon and PFAS are add-ons.

Order the Tap Score well water test kit, from $209Already tested? Upload the report

Just want bacteria checked first? Tap Score coliform and E. coli test, $99. Coliform and E. coli are the tests every well needs every year.

Want a quick look before paying for a lab? Home well water test strips on Amazon check hardness, iron, pH and nitrate in minutes. They are a screen, not a result: arsenic, bacteria, uranium and PFAS need a certified lab.

Affiliate links: the merchant pays us a commission and the price is the same for you. It does not change what the data above says. As an Amazon Associate we earn from qualifying purchases.

Where to get it tested

Three routes, and all of them work. A mail-in kit from a certified lab is the simplest: the lab ships bottles, you fill them at the kitchen tap, and results come back by email. The full panel above is $209.

A local certified lab is the second route. Water Laboratory Certification Program from Montana DPHHS lists every lab certified for drinking water in Montana. Call ahead: some take walk-in samples, some ship bottles.

The Montana State Environmental Laboratory (DPHHS) tests private well water for residents, including a Basic Screen for $55 (coliform and E. coli bacteria, nitrate plus nitrite, and specific conductivity) and a Metals Screen for $135 (including arsenic, lead, uranium, and hardness). Details from the state

For questions about your well, Water Resources at Montana DEQ is the official source.

Already have results? Get the lab report read line by line, $29.

Testing by county

The contaminant most often over its limit in each county's public record, highest share first. Open a county for the full test list and its towns.

CountyTest first forOver the limit
Gallatin CountyArsenic52%
Valley CountyNitrate49%
Roosevelt CountyArsenic46%
Daniels CountyNitrate42%
Chouteau CountyNitrate40%
Stillwater CountyNitrate33%
Powell CountyArsenic28%
Cascade CountyNitrate25%
Jefferson CountyRadium (226 + 228)23%
Madison CountyArsenic23%
Silver Bow CountyArsenic23%
Teton CountyNitrate20%
Richland CountyFluoride19%
Deer Lodge CountyArsenic17%
Sheridan CountyArsenic16%
Lake CountyFluoride15%
Liberty CountyNitrate15%
Beaverhead CountyArsenic14%
Hill CountyNitrate14%
Dawson CountyNitrate14%
Sanders CountyFluoride14%
Lewis and Clark CountyUranium13%
Custer CountyFluoride13%
McCone CountyNitrate13%
Phillips CountyArsenic13%
Toole CountyNitrate12%
Treasure CountyNitrate12%
Garfield CountyNitrate10%
Fergus CountyNitrate9%
Petroleum CountyFluoride8%
Flathead CountyNitrate8%
Carter CountyNitrate7%
Yellowstone CountyNitrate7%
Judith Basin CountyNitrate6%
Powder River CountyArsenic6%
Musselshell CountyNitrate6%
Glacier CountyArsenic6%
Big Horn CountyLead5%
Rosebud CountyLead5%
Lincoln CountyNitrate4%
Sweet Grass CountyFluoride4%
Carbon CountyNitrate4%
Ravalli CountyArsenic4%
Blaine CountyLead3%
Prairie CountyNitrate3%
Wibaux CountyFluoride3%
Fallon CountyFluoride2%
Missoula CountyNitrate2%
Broadwater CountyFluoride0%

Closer than the county: see the sampled wells near your address.

Free, no obligation

Get on the list for a free in-home water test in Montana

We are signing licensed water treatment companies county by county. They test at your tap for free, walk you through the numbers, and quote treatment only if something needs fixing. Nothing is shared until a company joins for your area, and you get an email naming it first.

What are you worried about?

The test is free and there is no obligation. No company is named yet; your details stay with us until one joins for your area, and we log the time and address of this request.

Common questions

What should I test my well for in Montana?

Start with nitrate, arsenic, uranium. 11% of 8,286 local samples were above the limit. Add total coliform bacteria and nitrate every year for any private well.

Where can I get my well water tested in Montana?

Use a lab certified for drinking water. Montana DPHHS keeps the list of certified labs. A mail-in kit from a certified lab works anywhere in the state.

How much does well water testing cost in Montana?

A full mail-in panel from a certified lab costs $209 (Tap Score well water test kit). A bacteria-only test costs $99 (Tap Score coliform and E. coli test). The Montana State Environmental Laboratory (DPHHS) tests private well water for residents, including a Basic Screen for $55 (coliform and E. coli bacteria, nitrate plus nitrite, and specific conductivity) and a Metals Screen for $135 (including arsenic, lead, uranium, and hardness).

How often should a private well be tested?

Bacteria and nitrate every year. A full panel once, then again after flooding, a change in taste, smell or color, work on the well, a new baby in the house, or a nearby result above the limit. Contaminants that come from the rock, like arsenic, radon and uranium, change slowly, so one good test and a check every few years is enough.