DeKalb County Property Tax Appeal, Illinois

Travis Bunn·Updated July 24, 2026

DeKalb County is located in northern Illinois, approximately 63 miles west of Chicago, with Sycamore serving as the county seat. As of the 2020 census, the county had a population of 100,420 residents. The largest city is DeKalb, home to Northern Illinois University, with other notable communities including Sycamore, Cortland, and Genoa. Property tax appeals matter significantly in DeKalb County because residents face one of the highest tax burdens in the nation, with an effective tax rate of 2.22% to 2.44% compared to the national median of 1.02%, resulting in median annual tax bills that are more than double the national average.

Notable cities: DeKalb, Sycamore, Cortland, Genoa

Median Home

$222,627

Tax Rate

2.22%

Annual Tax

$5,381

Population

100,420

On the typical DeKalb County home, valued near $222,627 at the county’s effective tax rate of 2.22%, an over-assessment of even 10% means you are overpaying year after year until you appeal it. Here is how to find out if yours qualifies.

2026 Appeal Deadline: 30 days after assessment roll publication in local newspapers

In DeKalb County, the assessment roll is published in local newspapers after the Chief County Assessment Office completes its review. Property owners have 30 days from the publication date to file an appeal with the Board of Review. The 2025 assessment publication occurred in October 2025 with a deadline of November 3, 2025. For 2026 assessments, the publication will occur in fall 2026. Individual notices are mailed to property owners whose assessments changed. It is strongly recommended to contact your Township Assessor first before filing a formal appeal.

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Aerial view of an Illinois residential neighborhood. DeKalb County appeal guide.

How DeKalb County Assesses Property

33.33%of market value

Assessed by: DeKalb County Chief County Assessment Office

Assessment cycle: annual

Notices typically mailed: Spring (notifications sent after assessment roll is published)

Illinois law requires all property to be assessed at 33.33% of its fair market value. If your home's market value is $222,000, at Illinois's 33.33% assessment ratio your assessed value would be approximately $74,000. At DeKalb County's effective tax rate of 2.22%, this results in approximately $1,643 in annual taxes before exemptions. The assessment ratio is applied uniformly across all residential properties in the county.

The Appeal Process

Appeals are heard by the Board of Review. Board of Review hearings are held in an informal setting at the Administration Building. The Board reviews evidence from both the property owner and the assessor, then makes a decision to confirm, reduce, or adjust the assessed value. Written decisions are mailed to appellants after all hearings for a township are completed.

Step 1: Contact your Township Assessor first to discuss your assessment informally. Many issues can be resolved at this level without filing a formal appeal. Your Township Assessor can explain why your assessment changed and review property details.

Step 2: Monitor local newspapers for the publication of the assessment roll, typically occurring in fall. The publication date starts your 30-day appeal window. You can also check the DeKalb County Assessment Office website for Publications & Deadlines.

Step 3: Obtain the Board of Review Complaint Appeal Packet by calling (815) 895-7120 or visiting https://dekalbcounty.org/departments/assessment-office/board-of-review/. Review the current DeKalb County Board of Review Rules before filing.

Step 4: Gather supporting evidence for your appeal, including comparable sales data from similar properties in your neighborhood, photographs documenting property condition or defects, recent appraisals, repair estimates for needed work, or documentation showing incorrect property characteristics (square footage, number of rooms, etc.).

Step 5: Complete the appeal forms and submit them with all supporting evidence to the Board of Review before the deadline. The appeal and evidence must be received or postmarked by the deadline date. Incomplete forms may result in dismissal.

Step 6: Attend your Board of Review hearing at the DeKalb County Administration Building, 4th Floor. The Board will review your evidence and the Township Assessor's information. Hearings are informal and open to the public.

Step 7: If you are dissatisfied with the Board of Review decision, you may appeal to the Illinois Property Tax Appeal Board (PTAB) within 30 days of receiving the Board of Review's written decision.

Step 8: As a final option, if still unsatisfied after PTAB review, you may appeal your assessment in circuit court according to Illinois property tax law.

Required form: DeKalb County Board of Review Complaint Appeal Packet

Filing Methods

mail:DeKalb County Chief County Assessment Office, 110 E. Sycamore Street, 4th Floor, Sycamore, IL 60178

in-person:Administration Building, 110 E. Sycamore Street, 4th Floor, Sycamore, IL 60178. Hours: 8:30 AM - 4:30 PM

email:Contact office at (815) 895-7120 for email submission instructions

Evidence to Bring

Comparable sales data from similar properties in your neighborhoodPhotographs documenting property condition or defectsRecent independent appraisal (if available)Repair estimates for needed maintenance or improvementsDocumentation of incorrect property details (square footage, rooms, features)Market analysis showing fair market value is lower than assessed value

DeKalb County Assessor Contact

DeKalb County Chief County Assessment Office

Website: https://dekalbcounty.org/departments/assessment-office/

Online Portal: https://dekalbil.devnetwedge.com/

Hours: 8:30 AM - 4:30 PM, Monday through Friday

Tax Exemptions in DeKalb County

General Homestead Exemption

$6,000 reduction in assessed value

Reduces the equalized assessed value (EAV) of owner-occupied primary residences

Eligibility: Property must be occupied as the primary residence by the owner as of January 1, and the owner must be liable for paying real estate taxes. Must have legal or equitable interest in the property. One-time application, does not need annual renewal.Deadline: Can be filed anytime during the assessment year

Senior Homestead Exemption

$5,000 reduction in assessed value (statewide standard)

Additional exemption for homeowners age 65 and older, claimed in addition to the General Homestead Exemption

Eligibility: Must be 65 years of age or older by the end of the tax year. Must own and occupy the property as primary residence as of January 1. One-time application with proof of age required.Deadline: Can be filed anytime during the assessment year

Senior Citizens Assessment Freeze

Freezes EAV at qualifying year level

Freezes the equalized assessed value at the level when first qualified, preventing increases due to rising property values

Eligibility: Must be 65 years or older and have total household income of $75,000 or less for 2026 tax year, $77,000 for 2027, $79,000 for 2028 and after. Must have used property as principal residence for previous and current year. Requires annual renewal.Deadline: Annual application required by June 1

Disabled Persons Homestead Exemption

$2,000 reduction in assessed value

Reduces assessed value for homeowners with qualifying disabilities

Eligibility: Must have a disability certified under federal standards. Must own and occupy property as primary residence. Documentation required.Deadline: Can be filed anytime during the assessment year

Standard Homestead Exemption for Veterans with Disabilities

30-49% disability: $2,500 EAV reduction; 50-69% disability: $5,000 EAV reduction; 70%+ disability: first $250,000 of EAV exempt (total exemption from taxes for most homes)

Tiered exemption based on VA service-connected disability rating

Eligibility: Must be Illinois resident who served in U.S. Armed Forces with at least 30% service-connected disability certified by VA. Must own and occupy as primary residence. Surviving spouses eligible if not remarried. Annual renewal required.Deadline: Annual application required

Specially Adapted Housing Exemption for Disabled Veterans

Up to $100,000 of assessed value exempt

Exempts up to $100,000 of assessed value for specially adapted housing

Eligibility: Federal funds must have been used for purchase or construction of specially adapted housing to meet disability needs. Also available for mobile homes. Apply through Illinois Department of Veterans' Affairs. Annual renewal required.Deadline: Annual application required

Returning Veterans' Homestead Exemption

$5,000 reduction in EAV for two consecutive years

Temporary exemption for veterans returning from active duty in armed conflict

Eligibility: Must have returned from active duty in an armed conflict involving U.S. armed forces during the tax year. Available for the return year and the following year.Deadline: File Form PTAX-341 with Chief County Assessment Office

DeKalb County Appeal Packet · $49

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Frequently Asked Questions

What is the deadline to appeal my property taxes in DeKalb County, Illinois?

In DeKalb County, you have 30 days from the date the assessment roll is published in local newspapers to file an appeal with the Board of Review. For 2025 assessments, the deadline was November 3, 2025. The publication typically occurs in October or November each year. If you received an individual assessment change notice, the 30-day window begins from the publication date, not your notice date. You can find specific publication dates and deadlines at https://dekalbcounty.org/departments/assessment-office/board-of-review/publications-deadlines/. Missing this deadline means you must wait until the next assessment year to appeal.

How do I file a property tax appeal in DeKalb County?

To file an appeal in DeKalb County, first contact your Township Assessor informally to discuss your assessment, as many issues can be resolved without a formal appeal. If you still wish to appeal, obtain the Board of Review Complaint Appeal Packet by calling (815) 895-7120 or downloading it from the county website. Complete the forms with your grounds for appeal (inaccurate market value, inequitable assessment, or incorrect property description) and attach supporting evidence such as comparable sales data, photos, or appraisals. Submit your completed appeal to the Chief County Assessment Office at 110 E. Sycamore Street, 4th Floor, Sycamore, IL 60178, either by mail, email, or in person before the 30-day deadline. Appeals can also be delivered to the office during business hours (8:30 AM - 4:30 PM). Make sure your appeal is received or postmarked by the deadline, as late appeals may be dismissed.

What is the homestead exemption worth in DeKalb County?

The General Homestead Exemption in DeKalb County reduces your property's assessed value by $6,000. With DeKalb County's effective tax rate of approximately 2.22%, this exemption saves homeowners roughly $133 annually. If you're 65 or older, you can claim an additional Senior Homestead Exemption worth $5,000 in assessed value reduction (approximately $111 in annual savings), for a combined savings of about $244 per year. Illinois seniors with household income of $75,000 or less in 2026 can also qualify for the Senior Assessment Freeze, which locks in your assessed value and can provide much larger savings over time as property values rise. These exemptions require only a one-time application and automatically renew each year, though the Senior Freeze requires annual income verification.

When are property assessment notices mailed in DeKalb County?

DeKalb County property assessment notices are mailed in the spring after Township Assessors complete their annual reassessments and turn the assessment roll over to the Chief County Assessment Office. Individual written notices are sent to property owners whose assessments have changed from the previous year due to reassessment by the Township Assessor, changes by the County Mapping Department, or revisions by the Chief County Assessment Officer. The assessment roll is then published in local newspapers, typically in October or November, which starts the 30-day appeal period. If your property's only change is due to a township-wide equalization factor or multiplier, you may not receive an individual notice, but the factor will be published in local newspapers. You can also check your property assessment online year-round at https://dekalbil.devnetwedge.com/.

What evidence do I need to win a property tax appeal in DeKalb County?

To succeed with a DeKalb County property tax appeal, you need compelling evidence showing your assessment is inaccurate or inequitable. The strongest evidence includes recent comparable sales data from at least three similar properties in your neighborhood that sold for less than your assessed market value (divide your assessed value by 0.3333 to get market value). Photographs documenting property defects, needed repairs, or unfavorable conditions that reduce value are also persuasive. A recent independent appraisal from a licensed appraiser can be very effective, though it involves cost. Documentation showing incorrect property characteristics (wrong square footage, number of rooms, or features listed) provides clear grounds for correction. You can research comparable properties using the county's online property search at https://dekalbil.devnetwedge.com/ or real estate websites. The more detailed and objective your evidence, the better your chances of a successful reduction at the Board of Review hearing.

Can I appeal my DeKalb County property taxes if my market value is correct but my taxes are still too high?

Yes, you can appeal based on inequitable assessment even if your market value is accurate. Illinois law allows appeals on grounds that your assessment is not uniform compared to other similar properties in the same neighborhood. This means if comparable homes have lower assessed values relative to their market values, you have grounds for an appeal. To pursue this type of appeal in DeKalb County, you'll need to provide evidence showing your property's assessment ratio (assessed value divided by market value) is higher than the typical ratio for comparable properties in your area. Gather assessment and sales data for at least three similar properties that recently sold, calculate their assessment ratios, and demonstrate the disparity. This type of evidence can be compelling at Board of Review hearings. You cannot appeal simply because your tax bill is high due to high tax rates, appeals must be based on assessment value, not the tax rate itself.

What happens after I file an appeal with the DeKalb County Board of Review?

After filing your appeal with the DeKalb County Board of Review, your case will be scheduled for a hearing at the Administration Building, 4th Floor, in Sycamore. Hearing schedules are posted on the county website and displayed prominently in the Administration Building vestibule. At your hearing, which is informal and open to the public, you'll present your evidence to the three-member Board of Review explaining why your assessment should be reduced. The Board will also review information from the Township Assessor. You're limited to three minutes for public comments if you speak. After all hearings for your township are completed, the Board will mail you a written decision stating whether your assessment was confirmed, reduced, or adjusted. If you're dissatisfied with the decision, you have 30 days to appeal to the Illinois Property Tax Appeal Board (PTAB). The PTAB appeal forms are available from the Assessment Office or online at the PTAB website.

Are disabled veterans exempt from property taxes in DeKalb County?

Illinois offers substantial property tax relief for disabled veterans in DeKalb County through the Standard Homestead Exemption for Veterans with Disabilities. Veterans with a 30-49% VA service-connected disability rating receive a $2,500 reduction in assessed value; those with 50-69% receive a $5,000 reduction; and veterans with 70% or higher disability rating receive a complete exemption on the first $250,000 of equalized assessed value, which effectively eliminates property taxes on most homes since Illinois assesses at 33.33% of market value. This means a 70%+ disabled veteran could own a home worth up to $750,000 at market value and pay zero property taxes on it. The exemption also applies to the veteran's spouse and unmarried surviving spouses. However, this exemption requires annual renewal, you must reapply each year with documentation from the VA certifying your disability rating. Applications are submitted to the Chief County Assessment Office at (815) 895-7120.

Official Resources

DeKalb County Chief County Assessment Office →

Official county assessor website with exemption applications, Board of Review information, and assessment appeals resources.

DeKalb County Property Tax Inquiry System →

Search and view property assessments, tax bills, payment history, and property characteristics for any parcel in DeKalb County.

Illinois Department of Revenue - Property Tax →

State-level property tax information including exemption details, forms, and appeal procedures for all Illinois counties.

DeKalb County Board of Review - Publications & Deadlines →

Current assessment publication dates and appeal filing deadlines by township for DeKalb County.

For state-wide appeal information including Illinois's assessment ratio and deadlines, see our Illinois Property Tax Appeal Guide →

Considering professional help with your appeal? Compare pricing, coverage, and pros/cons in our Best Property Tax Appeal Services (2026) or browse side-by-side service comparisons →

Looking for help in Illinois? Compare Illinois property tax appeal services →

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← All Illinois property tax appeal info

Sources: https://dekalbcounty.org/departments/assessment-office/ | https://dekalbcounty.org/departments/assessment-office/board-of-review/assessment-appeal/ | https://tax.illinois.gov/localgovernments/property/taxrelief.html | http://www.tax-rates.org/illinois/dekalb_county_property_tax | https://www.ownwell.com/trends/illinois/dekalb-county | https://dekalbil.devnetwedge.com/

Last verified: 2026-07-24