Why It Matters
Montana mobile home owners are receiving property tax bills up to three times higher than last year, providing the first indication of how the state’s new property tax system is affecting residents. County treasurers warn that financially vulnerable homeowners who failed to opt in for lower rates now face bills they may not be able to afford.
While this story centers on Montana, Idaho lawmakers have debated similar property tax reform proposals in recent sessions, making the Montana experience relevant for Idaho policymakers and property owners.
What Happened
Yellowstone County Treasurer Hank Peters discovered the problem on April 20 while preparing property tax bills for mobile home owners. The bills showed collections far higher than the previous year.
County treasurers from Yellowstone, Missoula, Gallatin, Valley and Jefferson counties confirmed the trend in recent interviews. They attributed the increases to legislation passed during Montana’s 2025 legislative session that required homeowners to opt in for preferential tax rates.
Large numbers of mobile home owners did not enroll for the lower rates, leaving them taxed as second homes at significantly higher rates. One mobile home in Billings saw taxes jump from $678 in 2025 to $1,941 in 2026. Another in Frenchtown increased from $561 to $1,574.
By The Numbers
- Property taxes for one Billings mobile home increased nearly threefold, from $678 to $1,941
- A Frenchtown mobile home’s taxes rose from $561 to $1,574
- Montana auto-enrolled 230,000 property owners who claimed a 2025 rebate
- 80% of Montana homeowners saw at least a 5% decrease in their 2025 bills
- Mobile home tax bills are mailed months earlier than other residential property
Zoom Out
Montana Governor Greg Gianforte and Republican legislators promised property tax reform at the start of the 2025 session. After months of debate, lawmakers passed legislation that created different tax rates for primary residences, long-term rentals, second homes and short-term rentals.
The new system requires homeowners and long-term rental owners to apply through the state Department of Revenue for lower rates under a homestead exemption. Those who do not successfully opt in are assessed at the higher rate applied to second homes.
Jefferson County Treasurer Terri Kunz expressed concern about mobile home owners’ ability to pay. Missoula County Treasurer Tyler Gernant noted that mobile home owners are already financially stretched, making even small increases significant.
Governor’s office spokesperson Kaitlin Timken defended the state’s outreach efforts, stating that the Department of Revenue launched a substantial campaign to inform homeowners about the changes and application requirements.
Gernant suggested some increases may stem from errors in the Department of Revenue’s systems. Montana offered $400 rebates in 2025 to residents living in primary homes, and those who claimed the rebate were supposed to be automatically enrolled in lower 2026 rates. Gernant reported seeing cases where the exemption did not carry over properly.
What’s Next
Mobile home tax bills are being mailed this month. County treasurers expect complaints from homeowners facing unexpected increases.
Tax bills for other residential property owners will be sent later this year, potentially revealing whether similar enrollment gaps affected a broader range of homeowners. Gallatin County Treasurer Maureen Horton predicted significant pushback from affected residents.
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