Indiana Commercial Property Owners: Why 2026 Assessments Are Increasing — And Why Appeals Matter More Than Ever

Commercial property owners across Indiana are beginning to receive their 2026 Form 11 assessment notices, and many are seeing a familiar trend: higher assessed values.

What’s driving these increases? In many cases, it’s not necessarily changes to the property itself or dramatic shifts in income performance—it’s a statewide update to the cost valuation models used by assessors.

What Changed?

The Indiana Department of Local Government Finance (DLGF) has historically relied on cost tables that many county assessors considered outdated and disconnected from modern construction economics. Beginning in 2025 and continuing into 2026, the DLGF has implemented updated cost schedules intended to better reflect current building costs and construction assumptions.

As one Indiana assessor recently explained:

“The DLGF has historically maintained a very outdated cost product provided to all 92 county assessors. There has been nearly universal agreement among county officials that these tables produce values that deviate from market norms. Last year and moving forward, the DLGF has committed to a more regular update process to include more recent build data and modern construction assumptions.”

The result? Broad increases in replacement cost new less depreciation (RCN-D) values across commercial real estate.

Why This Matters for Property Owners

While modernization of assessment models may sound reasonable in theory, mass appraisal systems are still just that—mass models. These cost-driven increases are often:

• Applied broadly across property types and markets
• Based on generalized assumptions
• Less sensitive to real-world property conditions
• Disconnected from actual income performance or market value

In other words, a higher assessment does not automatically mean the value is accurate. Properties with deferred maintenance, functional obsolescence, leasing challenges, market softness, or unique operational limitations may now be assessed well above what the market would truly support.

2026 Could Be a Critical Appeal Year

Whenever valuation methodologies change on a large scale, the likelihood of overassessment increases. That makes proactive review critical. Commercial property owners should carefully evaluate:

• Whether the assessed value aligns with actual market conditions
• Whether the cost assumptions properly reflect the property
• Whether depreciation and obsolescence have been accurately considered
• Whether comparable market evidence supports the assessment

Important Deadline: June 15, 2026

Indiana property owners should also be aware that the deadline to appeal 2026 assessments is June 15, 2026. Waiting too long can limit options and create unnecessary pressure as appeal volumes increase statewide.

Need Help Reviewing or Appealing Your Assessment?

Our team specializes in reviewing and challenging commercial property tax assessments. We analyze:

• Market value indicators
• Income performance
• Cost approach assumptions
• Property-specific characteristics
• Assessment uniformity and supportability

Our objective is simple: ensure property owners are taxed on fair, defensible values—not inflated mass appraisal assumptions.

If you think a commercial property is over-assessed—or want a second set of eyes on it— McGuire Sponsel can help you and your clients evaluate the situation and determine your best next step. A quick review can often uncover opportunities most owners miss.

Click here to contact us for a complimentary property review.
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