If you're closing on a home in the Madison County slice of Big Sky this year, look closely at the tax breakdown on your settlement statement. Somewhere in there, until very recently, was a line funding a hospital and a school district roughly ninety minutes away, over a mountain range, in a town called Ennis. Most buyers never ask what that line is for. The ones who do usually assume it's a mistake.

It isn't. It's the byproduct of how Big Sky was built: fast, valuable, and unincorporated, with district boundaries drawn decades before anyone imagined a ski town this expensive sitting on the wrong side of a county line. Buyers hear "no city government" and picture something simple. What actually exists is closer to the opposite, and 2025 and 2026 have been the two years that patchwork finally started getting rewritten.

The map nobody hands you at closing

Big Sky sits across two counties, Gallatin and Madison, and neither one has a mayor's office to call. Instead, a set of special districts split the work a city hall would normally do. The Big Sky Resort Area District, known locally as BSRAD, collects a 4 percent resort tax on lodging, restaurants, and luxury retail, a rate that started at 3 percent when voters created it in 1992 and rose to 4 percent after a 2020 ballot measure dedicated the new percentage point specifically to infrastructure. Alongside BSRAD sit the Big Sky Water and Sewer District and the Big Sky Fire District, each with its own board and its own assessment. One local columnist who spent a day touring the community's governance structure put the total count at a dozen or so overlapping special districts, working alongside the county, to run a town that has no town government.

That resort tax is worth separating from everything else on your bill. It's a sales tax, paid mostly by visitors at restaurants and hotels, and it funds BSRAD's own priorities: trails, transit, the library, workforce housing. Your property tax bill is a different animal entirely, built from mill levies that fund the county, the fire and water districts, and, depending on which side of the county line your parcel sits, a hospital and a school district that until this year had almost nothing to do with Big Sky day to day.

Ninety minutes over the Madison Range

The reason a Big Sky property tax bill has funded an Ennis hospital and an Ennis school district for years comes down to when the lines were drawn. Madison Valley Medical Center has served the Ennis area for about 75 years. Big Sky's Madison County side has existed for roughly 50. The hospital and school district boundaries predate the golf courses, the private ski terrain, and the assessed values that now make up most of the tax base flowing into both districts. Getting from Big Sky to Ennis means driving up and over Jack Creek Road, a long, winding, privately held route, or the longer paved detour around the range. Getting to Madison Valley Medical Center or an Ennis school board meeting is not a short errand for anyone living in Big Sky.

That geographic gap turned into a financial one. According to figures cited during the 2025 legislative debate over the arrangement:

Big Sky supplies roughly 87 percent of the property tax base for the Ennis-area hospital and school districts. It holds about 4 percent of the county's registered voters.

Put another way, the people paying for most of the service have almost no say in how it's run, and most of them will never use the hospital or send a child to the school their taxes fund.

What actually changed in 2025

State Senator Greg Hertz sponsored Senate Bill 260 to address exactly this kind of mismatch statewide, and it passed in April 2025. SB260 opened a formal path for an area to petition its way out of a hospital or school district when a genuine geographic barrier, like a mountain range, blocks access to the services that district provides.

On the hospital side, Big Sky moved fast. Voters in both counties were asked this spring whether to formalize a Big Sky Hospital/Wellness District, with Gallatin County residents voting on whether to create it and Madison County residents voting on withdrawal from the Madison Valley Hospital District. To keep the transition from hitting Ennis all at once, SB260 built in an eight-year step-down: the new district keeps sending a shrinking share of its collections back to Madison Valley Medical Center, starting at 70 percent in year one and tapering down to 20 percent by the final years, rather than cutting the hospital off overnight.

The school side moved on a slower track. A petition to withdraw the Madison County portion of Big Sky from Ennis School District only began circulating this past June, and it needs either agreement from both school boards or 325 signatures out of roughly 538 eligible residents to force a hearing. If it succeeds, the affected area splits its school tax dollars and any levies between Big Sky School District and Ennis School District for three years while the transition plays out.

There's a number buried in Montana Department of Revenue figures that explains why Ennis has been reluctant to let this money go. Ennis School District's taxable value sits near $619 million, largely inflated by Big Sky real estate, which is why its residents pay just 3.51 mills toward their schools' general fund. Compare that to Twin Bridges, a nearby district with about $6.14 million in taxable value, where residents pay 104.9 mills for the same kind of funding. A low mill rate quoted for a school district isn't always a sign of a lean, well-run budget. Sometimes it's a sign that someone else's expensive real estate is doing the work.

What incorporation would actually cost

Underneath all of this sits a bigger, slower-moving question: should Big Sky incorporate as its own town. BSRAD spent $329,750 in resort tax dollars, not property tax dollars, to fund a 2025 Governance Study from WGM Group, ECOnorthwest, and M2O Group, built specifically to put real numbers in front of residents rather than push a recommendation either way.

The study modeled three paths against the status quo, and each one keeps the resort tax fully intact. Only the layer on top of it changes.

Under the new-county model, anyone living in the surrounding county area but outside the incorporated core would pay a lighter 29-mill county tax instead, a reminder that where your specific parcel falls relative to a future boundary line would matter as much as it does today.

One detail worth sitting with: the study found that only Meadow Village, Town Center, and Mountain Village currently meet the population density Montana code requires to support basic incorporation. If a vote ever happens and passes, the first city limits in Big Sky's history would likely start there, leaving Spanish Peaks Mountain Club, Moonlight Basin, and much of the Canyon outside any new municipal boundary even after the fact.

The next line item is already forming

None of this is finished. In June 2026, BSRAD's board set aside $200,000 to hire consultants exploring a Targeted Economic Development District paired with tax increment financing, aimed at three specific problems: transportation, water and sewer capacity, and wildfire management. Board members pointed to the Cold Smoke housing development and the long-discussed canyon sewer project as examples of costs the resort tax alone can't cover. The tax stack that governs Big Sky today is not the same one that governed it three years ago, and it's unlikely to be the same one three years from now.

What this means when you're comparing neighborhoods

A generic property tax rate quoted for "Big Sky" tells you almost nothing useful, because your actual carrying cost depends on which county line runs under the driveway, which fire and water district serves the parcel, and, for now, whether the Madison County transition affects your specific school and hospital assignment. Before comparing carrying costs across Spanish Peaks Mountain Club, Moonlight Basin, Mountain Village, and the Meadow, ask which special districts actually apply to the parcel you're looking at, not the neighborhood in general. Staying current on these questions is part of why our own broker sits on the board of the Big Sky Housing Trust, one of the organizations working alongside BSRAD, the Water and Sewer District, and the Chamber on exactly these community-finance questions.

FAQ

Does Big Sky have property taxes if there's no city government? Yes. Property taxes still fund county government and the special districts that cover fire, water and sewer, and, depending on your parcel, a hospital and school district. The 4 percent resort tax is a separate sales tax that funds BSRAD specifically and doesn't appear on your property tax bill.

Is incorporation likely to happen soon? No vote is currently scheduled. The 2025 Governance Study was built to inform the community, not to recommend a path, and any future move toward incorporation would still need both legislative clearance and local voter approval.

If you're weighing a purchase anywhere in Big Sky and want to understand exactly which districts, mill levies, and pending changes apply to a specific property before you write an offer, Mia Lennon and Derek Lennon can walk through it with you parcel by parcel.