DeKalb County 2026: Auburn's Manufacturing Base and the BPP Exemption Lift

DeKalb County in northeast Indiana is built around manufacturing. Auburn — county seat, home of the Auburn-Cord-Duesenberg Automobile Museum — sits at the center of an industrial economy that includes auto parts, fabrication, and the cluster of suppliers serving northeast Indiana's larger automotive footprint. For DeKalb owners, the 2026 assessment cycle brings two structural changes that hit manufacturing-heavy counties harder than residential-only ones: the business personal property (BPP) exemption rising to $1M and the DLGF cost-table reset that drove statewide AVs up roughly 12% in 2025.

The 2026 Form 11 Notices of Assessment mail in mid-April, and the Form 130 appeal deadline is June 15, 2026 (or 45 days from the mailing, whichever is later). For a manufacturing-county economy like DeKalb's, the appeal cycle this year is more consequential than usual.

The BPP exemption is now $1M for the 2026 assessment year, climbing to $2M in 2027. Small Auburn-area shops, machine shops, and supplier operators with under $1M in business personal property no longer file a Form 103 BPP return. This is a permanent administrative simplification, not a temporary credit.

Why DeKalb Is a Manufacturing-Sensitive County

DeKalb's economy is unusually concentrated in industrial and commercial parcels relative to its population (~43,000). Auburn alone hosts a long-standing automotive manufacturing tradition, and the county's industrial corridors along I-69 and US 6 have grown around it.

Three structural items make DeKalb unusual:

In a typical Indiana county, residential AV is 60–75% of total AV. In DeKalb, the industrial and commercial share runs higher — closer to 35–45% of total AV depending on the specific tax district. That means cost-table reset pressure on industrial parcels has an outsized effect on the county's overall levy distribution.

Multi-Class Parcels Are Common

A DeKalb manufacturing site frequently includes a primary industrial building (class code 300-series), an office component (class code 400-series), warehouse (different class code), and undeveloped land held for expansion. Each component is assessed separately and each has its own cap tier — 2% for non-residential other than industrial, 3% for industrial. Class code drift in CAMA can move a parcel between tiers.

BPP Filing Was Historically a Material Burden

Before the 2026 exemption rise to $1M, even small Auburn machine shops with $50K of equipment had to file an annual Form 103. The $1M threshold (and $2M starting 2027) eliminates the filing requirement for the vast majority of small DeKalb operators.

What the BPP Exemption Lift Actually Means

The business personal property exemption applies to business-owned personal property — equipment, machinery, fixtures, and the like. It does not apply to real estate. The mechanics:

If your business owned less than $80,000 in BPP previously, you filed an exemption return
If your business owned between $80,000 and $1M in BPP for 2026, you no longer need to file a Form 103
If your business owned over $1M in BPP, you still file Form 103 and pay BPP tax on the full amount

For an Auburn-area machine shop with $300,000 of equipment, the change means:

Item	Before 2026	2026
Form 103 filing required	Yes	No
BPP tax on $300K	At county BPP rate	$0
Annual administrative cost	Several hours of accounting	Zero

This is a permanent change in the tax law, not a temporary credit. For DeKalb's small-to-mid-sized industrial base, it's a meaningful shift.

What's Different About Real Property Assessment in 2026

The BPP change is on the personal property side. Real property assessment in DeKalb still goes through the same Form 11 cycle as every other county.

The 2026 real property changes that hit DeKalb:

DLGF Cost-Table Reset

Statewide 12% AV growth in 2025 — DeKalb's residential AVs tracked broadly with the state, with above-median pressure on industrial parcels reflecting the construction-cost reset. A new manufacturing building that cost $80/sqft to build five years ago now costs $130/sqft, and the cost-table rebuild pushed assessed replacement values up correspondingly.

SB 1 $300 Homestead Credit

The SB 1 supplemental homestead credit caps at $300 — a meaningful percentage reduction for an Auburn homestead paying $1,500–$2,500 a year.

Supplemental Deduction Step-Up

35% to 40% of post-standard-deduction AV, applied automatically to homesteads on file.

Form 11 Items DeKalb Owners Should Verify

The full Form 11 day-of-arrival checklist applies. DeKalb-specific items:

Item	What to look for
Property class code	Industrial parcels: verify 300-series; office or warehouse should be separately classed
Improvement square footage	Manufacturing additions and equipment housing get added at reassessment
Land use code	Held-for-expansion land should be agricultural or vacant, not industrial
Neighborhood code	Auburn industrial corridors have specific neighborhood codes — verify match
Homestead status	Owners with Auburn homestead and a separate business address need both records correct

Appeal Strategy for Industrial Parcels

For Auburn-area industrial owners, the appeal calculus differs from residential:

Cost vs Income Approach

DeKalb (like most Indiana counties) defaults to the cost approach for industrial parcels. The 2025 cost-table reset drove cost-approach values up materially — but the income approach (capitalized rent and operating data) often produces a lower value, particularly for older buildings with deferred maintenance. A successful industrial appeal frequently hinges on demonstrating that income value sits below cost value.

Functional and Economic Obsolescence

A 30-year-old DeKalb manufacturing building still standing isn't worth its replacement-cost-new less depreciation if the layout doesn't match modern manufacturing flow requirements. Functional obsolescence (interior layout) and economic obsolescence (regional industrial vacancy or rent compression) both reduce assessed value when properly documented.

Comparable Sales

Industrial sales in DeKalb are infrequent enough that strict in-county comparable analysis is often impossible. Cross-county comparable sales — properly adjusted for local rate differences — are common in industrial appeals here.

The Indiana property tax appeal guide walks through the full Form 130 process. For industrial parcels, the practical advice is to engage with the assessor's office before formal filing — most DeKalb industrial appeals settle on written evidence rather than at hearing.

Residential Side: The SB 1 Credit Math

For an Auburn homestead with a $180,000 AV at typical DeKalb rates:

Step	Calculation	Amount
Gross AV	—	$180,000
Less standard	$48,000	$132,000
Less supplemental (40%)	40% × $132,000	$52,800
Net AV	—	$79,200
Tax rate (illustrative)	$20 / $1,000	—
Gross tax	$79,200 × 0.020	$1,584
1% cap test	1% × $180,000	$1,800 (cap not binding)
Pre-credit	min(gross, cap)	$1,584
SB 1 credit	10% × $1,584, max $300	$158
Final	$1,584 − $158	$1,426

This is illustrative — actual rates vary by DeKalb taxing district. For most Auburn-area homesteads, the cap is not binding and the SB 1 credit applies at the 10% rate, not at the $300 maximum.

DeKalb At a Glance

Metric	DeKalb County
Population (est.)	~43,000
Total parcels	~30,000
County seat	Auburn
School corporations	DeKalb Central, Garrett-Keyser-Butler, DeKalb Eastern
Industrial AV share	Above statewide median
Spring 2026 bill due	May 11, 2026
Form 11 mails	Mid-April 2026
Appeal deadline	June 15, 2026 (or 45 days from Form 11)

What to Do This Spring

For Auburn-area homestead owners: open the Form 11 the day it arrives, verify the five line items, and file Form 130 by June 15 if the AV looks unreasonable.

For Auburn-area industrial owners: the appeal calculus is more involved. Pull both cost-approach and income-approach values for your parcel, document any functional or economic obsolescence, and consider engaging the assessor's office informally before filing.

For small business owners with under $1M in BPP: enjoy the elimination of the Form 103 filing requirement starting with the 2026 assessment year. This is permanent.

Property Lookup pulls DeKalb parcel data including assessment history, and Tax Appeal Automation builds the Form 130 + evidence package for both residential and small commercial parcels.