How the well cost estimates are built

What an estimate is made of

Every estimate on this site adds up eight line items. Four belong to the drilling contract: drilling by the foot, casing by the foot, rig mobilization, and the well permit. Four finish the water system: the pump with its wire and drop pipe, the pressure tank and switch, the trench and line to the house, and a water quality test. A drilling-only estimate stops after the first four.

Each line item gets a low, a typical and a high figure. The three totals are the sums of those columns, rounded to the nearest hundred dollars. The national figures behind the cost to drill a well follow the same steps.

Depth from well completion reports

Depth drives the bill more than anything else, so we take it from records instead of guessing. Most states require the driller to file a completion report for every new well. We downloaded those exports from 35 state agencies and kept reports that meet all of these tests:

• a new well, not a deepening or repair, where the export says so
• a domestic or household use, where the export records use
• completed between 2016 and 2025 (a wider window in Connecticut, Indiana, Kentucky, Missouri, New York and North Dakota, where the recent files are small)
• a total depth between 20 and 3,000 feet

From the reports that pass, we take the 25th percentile, the median and the 75th percentile of depth for the state and for each county. A county gets its own row once it has 30 reports. Below that, the calculator uses the state figures and says so.

Sources¹

States without usable records

Fourteen states either publish no statewide completion data we could use or publish it in a form that does not give depth by county: Alabama, Arkansas, Georgia, Hawaii, Louisiana, Maryland, Mississippi, New Jersey, North Carolina, Pennsylvania, Rhode Island, South Carolina, Utah and Virginia. Their pages carry a thin-data notice.

For those states the depth comes from a national figure: for each of the three percentiles, the median across the 35 record states, one vote per state. The result is 100, 200 and 300 feet, built from 1,044,608 reports. One vote per state keeps a state with hundreds of thousands of reports from standing in for every state that has none.

West Virginia sits between the two groups. It publishes no completion reports in bulk, but the USGS keeps an inventory of groundwater wells in the state with their depths. That inventory has no water-use field, so it mixes household wells with monitoring, public supply and other wells. We use the 747 wells in it built from 1980 to 2025, since older wells run much shallower, and publish statewide figures only. Those wells stay out of the national figure above and out of the casing default.

Sources^1,2

Casing

Casing is the steel or PVC pipe that lines the hole down to competent rock or a sealed aquifer. Where a state's reports record casing length and at least 30 reports in the area do, we use the median casing length from those reports.

Where they don't, we assume casing runs 65% of the well's depth. That figure is the median ratio of casing to depth across the 24 states whose reports include casing. The spread is wide. In New England bedrock wells the casing stops near the top of the rock, around 6% of depth in Massachusetts and 11% in Connecticut and New Hampshire. In Arizona, Nevada and Texas casing runs nearly the full depth. A quote with much more or much less casing than our figure is not wrong on that basis alone.

Sources³

Prices from published rates

Completion reports record depth, not price. Prices come from rate bands we compile from public sources: price pages published by named drillers and pump installers, state cost-share programs that publish unit rates, state purchasing contracts, and lab fee schedules for water tests. Each band has a low and a high and names the source it came from. Twenty states have their own bands for at least some items. Everywhere else the national band applies, and the estimate says which one it used.

The national bands today are $25 to $75 per foot to drill, $10 to $45 per foot of installed casing, $1,000 to $4,000 for a submersible pump job, and $500 to $1,800 for a pressure tank. Every band is listed with its source on the sources page.

Sources^4,5,6

The formula

1. Low: 25th-percentile depth times the low drilling rate, plus casing times the low casing rate, plus the low end of each flat item.
2. Typical: median depth times the midpoint of the drilling band, plus casing times the midpoint casing rate, plus the midpoint of each flat item.
3. High: 75th-percentile depth times the high drilling rate, plus casing times the high casing rate, plus the high end of each flat item.

If you enter your own depth, all three columns use it and only the rates vary. If you enter a casing length, it replaces the records or the 65% assumption. The code that runs the calculator is the same code that builds the figures on every page.

The low and high totals pair a shallow well with low rates and a deep well with high rates. That makes the band wider than the spread you will see across three quotes for one site. Read it as the range for your area, and read the typical figure as the planning number.

Checking a quote

The quote check compares the total you were given with the low and high for your inputs and reports whether it falls below, inside or above the band. If you enter line items, each one is compared with its own band, and any of our eight items missing from your quote is listed. A missing item is often a real gap, like a quote that leaves out the pump, and sometimes a difference in how the driller bundles work, like casing folded into the per-foot rate.

Known gaps

• Completion reports describe wells that got drilled. Dry holes and abandoned attempts are under-reported, so the records lean toward successful wells.
• Published price pages come from drillers who choose to publish. Their rates may not match the busiest local outfits.
• Some states record a permit date rather than a completion date, so their year window is approximate. Wyoming and Colorado are in this group.
• Rates change faster than depth. Each rate band shows the year it was published, and we review the bands at least once a year.

The rules we follow for citing and updating figures are on the editorial policy page, and who runs the site is on the about page.