Montana property tax appeals
Review the sourced process overview below, then get the Montana DIY Appeal Kit with an evidence workbook, filing controls, official links, and an editable appeal letter in one PDF. No parcel-specific comps.
How a Montana appeal actually works
Every statement below is cited to its primary source and shows the date we verified it. Where we could not confirm something from a primary source, we say so instead of guessing. Dataset last re-verified 2026-08-13.
Missed the main deadline? Montana has 5 remedies most homeowners never hear about
County pages rarely surface these. Each one is a distinct legal route with its own clock.
Homestead / long-term rental reduced tax rate - ENROLLMENT IS MANDATORY AND WORTH MORE THAN MOST APPEALS
MCA 15-6-405 (effective January 1, 2026, enacted as Sec. 6, Ch. 767, Laws of 2025): 'Beginning in tax year 2026, the owner of a principal residence may apply to the department to receive the homestead reduced tax rate.' Owners who applied for and received the 2024 tax-year rebate under MCA 15-1-2305 through 15-1-2307 AUTO-QUALIFY; everyone else 'shall apply as provided in this section to receive the homestead reduced tax rate in tax year 2026.' Application is electronic or by mail on a department form 'between December 1 of the immediately preceding year and March 1'; mailed applications must be postmarked by March 1, and late applications roll to the following tax year. PROPERTY OWNED BY AN ENTITY (LLC, partnership, corporation, irrevocable trust) IS INELIGIBLE; only a grantor revocable trust may apply through its trustee. Once approved the status persists until sale, loss of principal-residence use, or application for a different residence. The Department of Revenue's live page confirms the enrollment window for tax year 2027 runs May 4, 2026 to March 1, 2027, and that qualification requires living in the property at least 7 months per year and being current on property taxes. Denials get an informal review (30 days), then CTAB, then MTAB under MCA 15-6-705.
When:
primary source · verified
Payment under protest - a prerequisite to any refund
MCA 15-1-402(2): 'A person appealing a property tax or fee pursuant to Title 15, chapter 2 or 15 ... shall pay the tax or fee under protest when due in order to receive a refund. If the tax or fee is not paid under protest when due, the appeal or mediation may continue but a tax or fee may not be refunded as a result of the appeal.' The protest must be in writing, made to the collecting officer before delinquency, specify the grounds, and generally not exceed the year-over-year increase. MCA 15-7-102(2)(b) requires the department's notice itself to warn of this. Missing the protest converts a winning appeal into a prospective-only adjustment - the customer wins and receives nothing back.
When:
primary source · verified
County commissioner refund of erroneous or illegal taxes
MCA 15-16-603(1): commissioners must order a refund of taxes 'paid more than once or erroneously or illegally collected if an appeal pursuant to 15-1-402 was not available,' on errors in the description or location of property or duplicate taxes, on MTAB or district court decisions under MCA 15-2-306, and on department assessment revisions under MCA 15-8-601. The taxpayer bears the burden of proving the refund is due; refunds under subsection (1)(c) run back 10 tax years or the duration of the error, and are barred if the taxpayer denied the department access to appraise.
When:
primary source · verified
Property Tax Assistance Program (PTAP)
MCA 15-6-305 provides graduated relief for fixed and limited income owners: 'The first $350,000 in market value of residential real property qualifying for the property tax assistance program is taxed at the rates established by 15-6-134 multiplied by' a 20%, 50% or 70% income multiplier. Income brackets are inflation-adjusted annually by the PCE factor and the $350,000 threshold is re-indexed after each reappraisal cycle. Eligibility requirements are set out in MCA 15-6-302.
When:
primary source · verified
Deemed-granted rule where the county board fails to hear a timely application
MCA 15-15-103(2)(a): if a County Tax Appeal Board refuses or fails to hear a timely application, the application 'is considered to be granted on the day following the county board's final meeting for that year.' This is a free win that should be docketed and monitored for every Montana file, in the same way California's two-year rule under Rev. & Tax. Code 1604(c) should be.
When:
primary source · verified
What evidence wins in Montana
MCA 15-8-111(1)-(2): 'All taxable property must be appraised at 100% of its market value,' market value being the willing-buyer/willing-seller price. For class four residential and commercial property the department must appraise under USPAP mass-appraisal standards, 'Comparable properties used for valuation must represent similar properties within an acceptable proximity of the property being valued,' and it must use the same valuation method for residential properties in the same neighborhood or subdivision absent a compelling reason. If the cost approach is used on residential property the department 'shall document why the comparable sales model does not support usage of the comparable sales approach' (MCA 15-8-111(3)(b)) - and that documentation is discoverable by the taxpayer under MCA 15-7-102(3)(c)(iii), which is the single strongest attack line in Montana. On objection, the department must disclose its methodology and data sources within 8 weeks, and on a signed confidentiality agreement must hand over the comparable sales data used and the sales data for the taxpayer's market model area (MCA 15-7-102(3)(b)-(c)). Both CTAB and MTAB 'may consider the actual selling price of the property, independent appraisals of the property, negative property features that differentiate the subject property from the department's comparable sales, and other relevant information' (MCA 15-7-102(6)). Assessment-to-assessment comparison is not an enumerated basis; the statutory theory is market value, not ratio.
primary source · verified 2026-08-12
The appeal ladder, in Montana's own terms
- 1
Montana Department of Revenue - informal classification and appraisal review (Form AB-26)
Deadline: For class three (agricultural), class four (residential/commercial) and class ten (forest) property: 'An objection must be made in writing or by checking a box on the notice within 30 days from the date on the classification and appraisal notice for a reduction in the appraised value to be considered for both years of the 2-year valuation cycle. An objection made more than 30 days from the date of the classification and appraisal notice will be applicable only for the second year of the 2-year valuation cycle.' Second-year objections must be made 'no later than June 1 of the second year of the valuation cycle or, if a classification and appraisal notice is received in the second year of the valuation cycle, within 30 days from the date on the notice.' All other property: 30 days from the date on the notice; centrally assessed property: 20 days. Note that Montana does not mail a notice every year - notices issue on change in ownership, classification, valuation, or affixed personal property.
Clock starts: Date printed on the Department of Revenue classification and appraisal notice
MCA 15-7-102(3)(a)(i)-(ii) · primary source · verified 2026-08-12
Form: AB-26 — Request for Informal Classification and Appraisal Review official form
primary source · verified 2026-08-12
Fee: none
MCA 15-7-102(3) prescribes no filing fee; the form is submitted to the Department of Revenue field office shown on the notice. · primary source · verified 2026-08-12
- 2
County Tax Appeal Board (CTAB)
Deadline: 'The appeal to the county tax appeal board, pursuant to 15-15-102, must be filed within 30 days from the date on the notice of the department's determination.' Where no AB-26 review was taken, MCA 15-15-102(3) requires the application to be filed 'within the time periods provided for in 15-6-418, 15-6-705, or 15-7-102(3)(a)' - that is, the same 30 days from the classification and appraisal notice. IMPORTANT CORRECTION TO STALE GUIDANCE: the older 'first Monday in June or 30 days from the notice, whichever is later' formulation is NOT in current law; MCA 15-15-102 as amended by Ch. 767 and Ch. 775, Laws of 2025, contains no June date. Only one application is permitted per valuation cycle (MCA 15-15-102(4)).
Clock starts: Date on the Department of Revenue determination following informal review, or the date on the classification and appraisal notice if no AB-26 was filed
MCA 15-7-102(6); MCA 15-15-102(3)-(4) · primary source · verified 2026-08-12
Form: MTAB Form 401 — Appeal to the County Tax Appeal Board official form
primary source · verified 2026-08-12
Fee: none
MCA 15-15-102 prescribes no filing fee; the application is filed with the county clerk and recorder, whose date stamp fixes the filing date (MCA 15-15-102(2)). · primary source · verified 2026-08-12
- 3
Montana Tax Appeal Board (MTAB)
Deadline: Appeal to MTAB must be filed 'within the later of: (i) 45 calendar days after the date of the county board hearing; or (ii) 30 calendar days after the date the county board mails its decision.' JURISDICTIONAL PREREQUISITE: the appeal is barred unless the taxpayer or the taxpayer's agent exhausted county remedies by ATTENDING the CTAB hearing (MCA 15-15-103(1)); attendance may be waived only on written request with the Department of Revenue's written concurrence. CAUTION: MTAB's own Form 801 states the shorter '30 days from when you received the decision' - the statute controls, but the safe practice is to file on the shorter of the two.
Clock starts: Date of the county board hearing, or the date the county board mails its decision
MCA 15-2-301(1)(b); MCA 15-15-103(1) · primary source · verified 2026-08-12
Form: MTAB Form 801 — Appeal to the Montana Tax Appeal Board official form
primary source · verified 2026-08-12
Fee: none
MCA 15-2-301; no filing fee appears on Form 801 or in the MTAB appeal-process instructions. · primary source · verified 2026-08-12
- 4
Montana district court (judicial review of MTAB)
Not confirmed from a primary source: The right of judicial review is confirmed by MCA 15-7-102(6), but the exact petition deadline (MCA 15-2-303 / 2-4-702) was not fetched in this session. Do not rely on a 30-day assumption. Check the official page before relying on this.Not confirmed from a primary source: A district court petition is a pleading, not an agency form; no official form located. Check the official page before relying on this.Not confirmed from a primary source: Title 25 fee schedule not fetched in this session. Check the official page before relying on this.
Who has to prove what
Preponderance (contested-case standard). MTAB review of annually assessed industrial property is de novo under the Montana Administrative Procedure Act.
primary source · verified 2026-08-12
When values are set
MCA 15-7-111(1)(a): 'all real property and all property within class three, class four, and class ten must be revalued every 2 years' and 'all other property must be revalued annually.' 'The reappraisal of class three, class four, and class ten property is complete on December 31 of every second year of the reappraisal cycle' (MCA 15-7-111(3)), and each county must be revalued 'by January 1 of the second year of the reappraisal cycle, effective for January 1 of the following year' (MCA 15-7-111(5)). An AB-26 objection filed within 30 days of the notice binds BOTH years of the cycle; filed later, it reaches only the second year - a direct, quantifiable reason to file early.
primary source · verified 2026-08-12
How counties differ
Deadlines are statewide by statute - there is no county variation in Montana, because valuation is performed by the state Department of Revenue rather than by county assessors. What varies is mechanics. CTAB applications are filed with the COUNTY CLERK AND RECORDER (not the Department of Revenue, not MTAB), and 'the date of receipt is the date stamped on the appeal form by the county clerk and recorder' (MCA 15-15-102(2)) - so mailing does NOT stop the clock at the county level and a mailed application must arrive, not merely be postmarked. CTAB hearings are held in the county seat, generally between July 1 and December 31. The AB-26 goes to the Department of Revenue field office printed on the notice.
Montana appeal deadline
Deadlines varyMontana deadlines are set locally.
The deadline is almost always printed on the assessment notice your local assessor mails you. Use that date, it is the one that counts.
Are you missing a Montana exemption?
Exemptions cut your bill before any appeal even starts, and most homeowners never claim all the ones they qualify for. Answer four questions:
Is your Montana home over-assessed?
The whole appeal hinges on one comparison: your assessed value (from your tax notice) versus your home's market value (what it would sell for today). Put both in:
How to find your home's real market value (free) →
- Pull free estimates. Look up your address on Zillow (“Zestimate”) and Redfin (“Redfin Estimate”). Average them, algorithms run high or low, so two beats one.
- Find 3-5 real comparable sales. Same neighborhood, similar size, beds/baths, age, and condition, sold in the last 6-12 months. Recent sales (not listings) are the strongest evidence a board will accept.
- Adjust for differences. Knock value off comps that are bigger or renovated; add for ones that are smaller or dated, so you're comparing like-for-like.
- Compare to your assessment. If your assessed value sits clearly above that adjusted market figure, you have grounds to appeal.
One catch: some states assess at a fraction of market value (an “assessment ratio”). If your notice shows a ratio or an “equalized” value, compare your implied full value to market, not the raw assessed number.
How property tax appeals generally work
Most states follow the same basic path: your local assessor mails an assessment notice with a value and a deadline; you file an appeal (often called a protest, grievance, or petition) before that deadline; you present comparable sales of similar homes; and a local board reviews the evidence and can lower your value.
The exact form, deadline, and board can vary by county. Use the current assessment notice and the official sources linked above to confirm the controlling local requirements. The paid kit organizes that verification, the evidence, the filing steps, and your editable letter in one place.
Want to see the depth we build per state? Take a look at our Texas, Florida, and Georgia guides.