How to Appeal Your Property Tax in Montana: Step-by-Step Guide for 2026

Montana’s property tax system is unusual, and understanding how it works is the first step toward knowing whether an appeal is worth your time. Unlike most states that simply multiply a property’s assessed market value by a tax rate, Montana applies a classification system where different property types are taxed at different percentages of market value. Use our rent affordability calculator for detailed numbers. Residential property is taxed at 1.35% of market value (the “taxable value”), and that taxable value is then multiplied by local mill levies that vary by county, city, school district, and special taxing jurisdictions. If your home’s market value assessment is too high — or your property is misclassified — you are overpaying, potentially by hundreds or thousands of dollars per year. This guide shows you exactly how to challenge your assessment in Montana for 2026, including deadlines, documentation, and what to expect at each step.

Montana reassesses all property statewide on a two-year cycle managed by the Montana Department of Revenue (DOR). The most recent reappraisal cycle completed in 2025, and the values from that cycle determine your 2025-2026 tax bills. If your assessed value jumped significantly in the latest cycle — and many Montana properties saw 20-40% increases reflecting the pandemic-era price boom — an appeal may be warranted. Use our property tax calculator to see how your assessed value translates into annual tax liability.

Step 1: Understand Your Tax Bill

Before appealing, make sure you understand what you are actually being charged and why. Request or download your property record from the Montana Department of Revenue. Key elements to review:

Example: A home assessed at $400,000 market value in Billings. Taxable value = $400,000 × 1.35% = $5,400. Total mill levy for that property’s taxing jurisdictions = approximately 550 mills. Tax = $5,400 × 550 ÷ 1,000 = $2,970.

If you believe the $400,000 market value is too high — say your home would realistically sell for $350,000 — a successful appeal reduces your taxable value to $4,725 and your tax to $2,599, saving $371 per year. Over 10 years, that is $3,710. The savings compound on more valuable properties.

Step 2: Gather Evidence

The strength of your appeal depends entirely on your evidence. The Montana DOR and local County Tax Appeal Boards base decisions on market data, not feelings about fairness. You need to demonstrate that your assessed market value exceeds what your property would actually sell for.

Best evidence for a Montana property tax appeal:

• Comparable sales: Find 3-5 similar homes in your neighborhood that sold within the past 12 months at prices below your assessed value. Comparable means similar in size, age, condition, lot size, and location. The Montana DOR publishes sales data through the Property Tax Assessment Lookup tool on their website.
• Current listing data: If similar homes in your area are listed at or below your assessed value, this supports a lower valuation — though listings are weaker evidence than actual sales because asking price is not guaranteed selling price.
• Professional appraisal: A full appraisal ($350-$500) from a licensed Montana appraiser provides the strongest evidence. The appraiser’s market value opinion carries significant weight with appeal boards. This is worth the cost if your potential savings exceed $500/year.
• Property condition issues: If your home has problems that reduce its value — foundation damage, an aging roof, outdated systems, structural issues — document them with photos and contractor estimates. The DOR assessment assumes typical condition for your property’s age and type.
• Errors in property records: Check your property record for factual errors — incorrect square footage, wrong number of bedrooms/bathrooms, finished basement counted incorrectly, or extra structures that do not exist. These errors inflate assessed value and are the easiest wins on appeal.

Step 3: File an Informal Review (AB-26 Form)

Montana’s appeal process starts with an informal review by the Department of Revenue. This is not optional — you must request informal review before proceeding to a formal appeal.

The informal review is your best chance for a quick resolution. DOR appraisers at the local level have the authority to adjust values based on evidence. Be organized: present your comparable sales, note any property record errors, and include photos if condition is relevant. Many appeals are resolved at this stage without needing to go further.

Step 4: Appeal to the County Tax Appeal Board (If Needed)

If the informal review does not result in a satisfactory adjustment, you can appeal to your County Tax Appeal Board (CTAB). This is a formal hearing before a local board of appointed citizens.

At the CTAB hearing, present your case clearly and concisely. Bring printed copies of your evidence for each board member. The DOR will present their justification for the assessed value. The board weighs both sides and issues a decision, typically within 30 days of the hearing. Board decisions can be appealed further to the Montana State Tax Appeal Board if you believe the CTAB erred.

Step 5: State Tax Appeal Board (Final Administrative Appeal)

If the CTAB decision is unsatisfactory, you can appeal to the Montana State Tax Appeal Board (STAB). This is the final administrative appeal before the court system.

• Filing deadline: Within 30 days of the CTAB decision.
• Process: Written briefs and, in some cases, a hearing before the state board in Helena (or via video conference).
• Cost: Free to file, but preparing a state-level appeal often benefits from professional help (attorney or tax consultant, $500-$2,000).
• Decision: The STAB issues a written opinion that is binding unless appealed to district court.

Most residential appeals are resolved at the informal review or CTAB level. State-level appeals are uncommon for typical residential properties and generally only worthwhile when significant tax dollars are at stake ($2,000+/year) or when a point of principle (such as property classification) affects many similar properties.

Common Reasons Montana Property Tax Appeals Succeed

When NOT to Appeal

An appeal is not always worth the effort. Do not appeal if:

• Your assessed value is at or below what your home would sell for on the open market. The DOR only needs to prove the assessed value is within a reasonable range of market value — not that it matches the exact price you believe your home is worth.
• Comparable sales support the assessed value. If three similar homes in your neighborhood sold within 5% of your assessment, you do not have a case.
• The potential savings are small (under $200/year). Your time and effort have value — spending 10 hours on an appeal to save $150/year is a poor return.
• You are appealing the mill levy, not the assessed value. Mill levies are set by local governments and cannot be changed through the property tax appeal process. They require voter action.

Tips for a Successful Montana Property Tax Appeal

• Meet every deadline. Montana’s appeal deadlines are strict — missing a 30-day window closes the door for that tax cycle. Mark the dates the moment you receive your assessment notice.
• Be factual, not emotional. Appeal boards respond to market data, property records, and professional opinions. Arguing that your taxes are “unfair” or that government spending is too high is not relevant to a property valuation appeal.
• Start at the county DOR office. The informal review is conversational, not adversarial. DOR appraisers at the local level are often willing to adjust values when presented with solid evidence. A confrontational approach is counterproductive.
• Get a professional appraisal for high-value properties. If your home is assessed above $500,000 and you believe it is overvalued by 10%+, a $400 appraisal that supports a lower value can save $500-$1,500/year in taxes. The ROI is immediate.
• Check your neighbor’s assessments. Montana’s property tax records are public. If similar homes on your street are assessed significantly lower than yours, that inconsistency is strong appeal evidence. Access records through the Montana Department of Revenue’s Cadastral Mapping application.

Use our mortgage calculator to see how a reduced property tax assessment affects your total monthly housing cost.

Compare With Other States

Considering other markets? Here’s how other states compare:

• How to Appeal Your Property Tax in Georgia: Step-by-Step Guide
• How to Appeal Your Property Tax in Missouri: Step-by-Step Guide
• How to Use Prop 13 to Lower Your California Property Taxes

Frequently Asked Questions

When do I receive my property tax assessment notice in Montana?

Montana sends assessment notices in the spring of reappraisal years (every two years). The most recent notices went out in 2025 for the 2025-2026 cycle. You have 30 days from the date on the notice to file an informal review request. If you did not appeal during the most recent cycle and the next reappraisal has not occurred, you can still request an informal review if you have new evidence of a value change (such as a sale of your property or comparable sales).

How much can I save by appealing my property taxes in Montana?

It depends on how far above market value your assessment is. A 10% reduction on a $400,000 assessment reduces your annual tax by approximately $300-$400. A 20% reduction saves $600-$800/year. On higher-value properties or in areas with higher mill levies, the savings can exceed $1,000/year. Over the remaining years of the assessment cycle, these savings multiply.

Can I appeal my property taxes every year?

You can request an informal review in any year if you have new evidence (such as recent comparable sales or a change in property condition). However, the formal appeal process through the CTAB is typically tied to the biennial reappraisal cycle. In practice, appealing after each reappraisal (every two years) is the most effective approach.

Should I hire a property tax attorney or consultant?

For most residential properties, no. The informal review and CTAB processes are designed for homeowners to navigate without professional help. However, if your property is assessed above $750,000, if the appeal involves a classification dispute, or if you are appealing to the State Tax Appeal Board, professional assistance ($500-$2,000) can be worth the investment. Some tax consultants work on a contingency basis, charging a percentage of the savings achieved.

Does appealing my property tax trigger additional scrutiny?

No. Filing an appeal is your legal right and does not trigger audits, additional assessments, or retaliation. The DOR reviews your specific property’s valuation based on the evidence presented. If the evidence supports a lower value, they adjust it. If it does not, the assessment stands. The process is straightforward and non-punitive.

What if I recently bought my home for less than the assessed value?

A recent arm’s-length purchase price is some of the strongest evidence available for an appeal. If you bought your home for $350,000 and it is assessed at $400,000, your closing documents (HUD-1 or Closing Disclosure) provide clear evidence of market value. Present these at the informal review stage. The DOR may still argue that your purchase price was below market (for example, a foreclosure or family sale), so be prepared to explain the circumstances. Your closing documents from the purchase serve as primary evidence.