Jefferson County, Montana: Power, Data Centers and the Local Economy
Home to Boulder and Whitehall
Jefferson County is not a build-out site today. It feels the boom through the grid it shares, the utilities that serve it and the work nearby. Construction employs 426, up 39.2% since 2019, and construction is 2.9 times as concentrated here as in the U.S. economy. Jefferson County is home to Boulder and Whitehall. Employers here counted 2,784 jobs in 2025, up 17.3% from 2019 (the 8th fastest growth of 56 Montana counties). Next door, Lewis and Clark County has 3 data centers. Unemployment was 2.6% in August 2026, against 3.4% in 2019.
Cities and towns in Jefferson County
Jefferson County is home to Boulder and Whitehall.
Unincorporated communities (governed by the county): Basin, Cardwell, Clancy, Elkhorn, Jefferson City, Montana City, Rader Creek, South Hills.
Residents are 2025 Census estimates for the part of each city, town or township inside this county. Census publishes no annual estimate for unincorporated communities.
What changed in Jefferson County
1st = the most. Ranks cover counties with a value on record.
| Measure | Then | Now | Change | Rank in Montana |
|---|---|---|---|---|
| Population (2020 → 2025) | 12,141 | 13,329 | ▲ 9.8% | 15th of 56 by size |
| Total jobs (2019 → 2025) | 2,373 | 2,784 | ▲ 17.3% | 8th of 56 by growth |
| Average annual pay (2019 → 2025) | $43,366 | $57,412 | ▲ 32.4% | — |
| Construction jobs (2019 → 2025) | 306 | 426 | ▲ 39.2% | 10th of 25 by growth |
| Unemployment rate (2019 → August 2026) | 3.4% | 2.6% | ▼ 0.8pts | — |
13,329 people live here, up 9.8% since 2020. NorthWestern Energy LLC - (MT) is the largest utility serving Jefferson County, one of 3 with territory here. Its residential customers paid an average 14.23¢/kWh in 2024, above the 10.95¢ median for Montana utilities.
Who powers Jefferson County
Utilities with service territory in Jefferson County
| Utility | Ownership | Service | Residential customers (systemwide) | Residential price, 2024 | Commercial share of sales |
|---|---|---|---|---|---|
| NorthWestern Energy LLC - (MT) | Investor Owned | Bundled | 328,127 | 14.23¢ | 49% |
| Bonneville Power Administration | — | — | — | — | — |
| Vigilante Electric Coop, Inc | — | — | — | — | — |
Customer counts, prices and sales shares cover each utility's whole system in the state, not only this county. Commercial sales include data centers.
No operating power plant is located in Jefferson County in the EIA-860M inventory. Its power comes over the grid from plants elsewhere.
The Jefferson County labor market
| Industry (2025) | Jobs | Average pay | Concentration vs U.S. |
|---|---|---|---|
| All industries | 2,784 | $57,412 | 1.00 |
| Construction | 426 | $60,130 | 2.89 |
Concentration is the BLS location quotient: 1.0 means the industry holds the same share of local jobs as it does nationally. Industry rows count private employers; cells BLS suppresses are left out.
Data centers and local rules in Jefferson County
No data center, local measure or delayed project is on record in Jefferson County. Montana has 5 local measures on record statewide, and 1 neighboring county has one: Silver Bow County.
Jefferson County and its neighbors
Of the 7 counties that border Jefferson County, Lewis and Clark County carries the most build-out activity: data centers, planned generation and operating plants combined.
| County | Population | Jobs since 2019 | Operating MW | Planned MW | Data centers | Local measures |
|---|---|---|---|---|---|---|
| Jefferson County | 13,329 | ▲ 17.3% | — | — | — | — |
| Broadwater County | 8,493 | ▲ 12.1% | 10 MW | — | — | — |
| Deer Lodge County | 9,709 | ▲ 7.6% | 203 MW | — | — | — |
| Gallatin County | 128,740 | ▲ 22.6% | 4 MW | — | 2 | — |
| Lewis and Clark County | 75,331 | ▲ 9.2% | 80 MW | 7 MW | 3 | — |
| Madison County | 10,026 | ▼ 32.7% | 16 MW | — | — | — |
| Powell County | 7,157 | ▲ 1.8% | — | — | — | — |
| Silver Bow County | 36,118 | ▲ 5.0% | 55 MW | — | — | 1 |
More of Montana
Jefferson County, answered from the record
Who provides electricity in Jefferson County, Montana?
3 utilities have service territory in Jefferson County in the EIA-861 2024 report: NorthWestern Energy LLC - (MT), Bonneville Power Administration, Vigilante Electric Coop, Inc. The largest, NorthWestern Energy LLC - (MT), charged residential customers 14.23¢/kWh on average in 2024.
Are there data centers in Jefferson County?
The SAVRN Data Center Map has no data center in Jefferson County. The nearest activity on record is next door in Lewis and Clark County.
Is Jefferson County adding jobs?
Employers counted 2,784 jobs in 2025 against 2,373 in 2019 (+17.3%, BLS QCEW). Construction went from 306 to 426.
Does Jefferson County have a data center moratorium?
No county-level measure is on record for Jefferson County. Montana has 5 local measures statewide, listed on the state page.