DeKalb County Property Tax Appeal — Illinois

Rob Hartley·Updated March 5, 2026

DeKalb County, Illinois is located in the northern part of the state with Sycamore serving as the county seat. The county is home to Northern Illinois University in DeKalb, one of the largest employers and educational institutions in the region. DeKalb County has a median home value ranging from approximately $192,300 to $247,000 depending on the source and time period, with an effective property tax rate of approximately 2.22% to 2.86%. This places DeKalb County's property tax burden significantly above the national median of 1.02%, making it one of the highest-taxed counties in Illinois, which itself has the highest property tax rates in the nation. For homeowners in DeKalb County, the median annual property tax bill ranges from $4,267 to $5,442, which is substantially higher than the national median of $2,400.

Notable cities: Sycamore, DeKalb, Genoa, Sandwich, Hinckley, Cortland

Median Home

$247,000

Tax Rate

2.22%

Annual Tax

$4,267

Population

105,000

2026 Appeal Deadline: 30 days from the publication date of the assessment notice for your township

Each township in DeKalb County publishes assessment notices annually, typically in spring. Property owners have 30 days from the date their township's assessments are officially published to file an appeal with the Board of Review. If the deadline falls on a weekend or holiday, it extends to the next business day. It is strongly recommended to first discuss the assessment with your Township Assessor before filing a formal Board of Review appeal.

Property in DeKalb County, Illinois — local tax assessment and appeal guide

How DeKalb County Assesses Property

33.33%of market value

Assessed by: DeKalb County Chief County Assessment Office and Township Assessors

Assessment cycle: annual

Notices typically mailed: April

In Illinois, property assessments are based on one-third (33.33%) of the property's fair market value. For example, if your home's market value is $247,000, at Illinois's 33.33% assessment ratio your assessed value would be $82,334. At DeKalb County's effective tax rate of 2.22%, this would result in approximately $5,472 in annual property taxes before any exemptions are applied. The assessed value is what gets multiplied by your local tax rate to calculate your actual tax bill.

The Appeal Process

Appeals are heard by the Board of Review. The Board of Review hearing is a quasi-judicial proceeding where both you (or your representative) and the Township Assessor present evidence supporting your respective positions on the property's fair market value or assessment equity. The Board members will review all evidence and issue a written decision, which you can further appeal to the Illinois Property Tax Appeal Board within 30 days if you disagree.

Step 1: Contact your Township Assessor first to review the assessment and potentially resolve the issue informally. Many assessment concerns can be clarified at this stage without needing to file a formal appeal.

Step 2: If not satisfied after speaking with the Township Assessor, obtain the DeKalb County Board of Review appeal forms from the county website at dekalbcounty.org or by calling (815) 895-7120. Determine your township's specific filing deadline, which is 30 days from the publication date.

Step 3: Complete the appeal form in its entirety, including your property information, current assessed value, and your requested assessed value. Gather supporting evidence such as comparable property assessments, recent comparable sales data, photographs, appraisals, or documentation of property defects or errors in the assessment records.

Step 4: Submit one complete original appeal form with all supporting evidence to the Board of Review by mail (postmarked by deadline) or in person at the Administration Building in Sycamore. No appeals are accepted via email or fax. Choose your hearing preference: waive oral hearing, teleconference, in-person, or virtual.

Step 5: The Board of Review will schedule a hearing if you requested one. You will present your evidence and the Township Assessor will present their case. The Board of Review will issue a written decision on your assessment.

Step 6: If you disagree 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 notice. File using PTAB forms available at ptab.illinois.gov.

Step 7: If still dissatisfied with the PTAB decision, you may seek judicial review in circuit court under the Administrative Review Law within the time specified by law.

Required form: DeKalb County Board of Review Residential Appeal Form or Commercial Appeal Form

Filing Methods

mail:DeKalb County Board of Review, Administration Building, 110 E Sycamore St., 4th Floor, Sycamore, IL 60178. Must be postmarked by the deadline date.

in-person:DeKalb County Board of Review, Administration Building, 110 E Sycamore St., 4th Floor, Sycamore, IL 60178. Must be delivered by the deadline date during business hours 8:30 AM - 4:30 PM.

Evidence to Bring

Comparable property sales data from the past 6-12 months of similar properties in your areaAssessment data showing similar properties in your neighborhood assessed at lower values per square footProperty condition documentation including photographs showing defects, damage, or functional obsolescenceProfessional appraisal report conducted by a licensed appraiserProperty record card printout highlighting any errors in square footage, lot size, room count, or featuresRepair estimates or contractor invoices documenting needed repairs or recent damage

DeKalb County Assessor Contact

DeKalb County Chief County Assessment Office / Board of Review

Phone: (815) 895-7120

Address: Administration Building, 110 East Sycamore Street, Sycamore, IL 60178

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

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 of owner-occupied primary residences in DeKalb County by up to $6,000.

Eligibility: Must own and occupy the property as your primary residence as of January 1 of the tax year. This is a one-time application and does not need annual renewal unless ownership changes.Deadline: Can be filed anytime during the assessment year

Senior Citizens Homestead Exemption

Up to $5,000 reduction in assessed value in counties outside Cook County

Additional reduction in equalized assessed value for senior citizens age 65 and older who own and occupy their home as their primary residence.

Eligibility: Must be 65 years or older during the assessment year and occupy the property as primary residence. May also qualify for the Senior Assessment Freeze if household income is under $65,000.Deadline: Can be filed anytime during the assessment year

Home Improvement Exemption

Up to $25,000 off the increased assessed value for up to 4 years

Exempts the increased assessed value from new improvements or additions to owner-occupied properties for up to four years.

Eligibility: Available for added improvements such as new garage, deck, central air, room addition, etc. to an owner-occupied property. Does not apply to general maintenance.Deadline: Should be applied for after improvement completion

Disabled Veterans' Standard Homestead Exemption

30%-49% disability: $2,500; 50%-69% disability: $5,000; 70% and above: tax exempt

Annual reduction in equalized assessed value for veterans with service-connected disabilities who occupy the property as their primary residence.

Eligibility: Must be a veteran with at least 30% service-connected disability certified by the U.S. Department of Veterans Affairs, receiving disability compensation. Must own and occupy property as primary residence.Deadline: Requires annual renewal

Disabled Veterans' Exemption for Specially Adapted Housing

$100,000 reduction in assessed value

Exempts up to $100,000 of assessed value for specially adapted housing owned and used by disabled veterans where federal funds were used for purchase or construction.

Eligibility: Available for certain types of housing owned and used by a disabled veteran or unremarried surviving spouse where federal funds were used for specially adapted housing purchase or construction. Contact Illinois Department of Veterans' Affairs to determine eligibility.Deadline: Must be reestablished annually

Disabled Persons' Homestead Exemption

$2,000 reduction in assessed value annually

Annual $2,000 reduction in equalized assessed value for persons with disabilities who own and occupy their primary residence.

Eligibility: The disabled person must occupy the property as primary residence, be liable for property taxes, and have ownership or legal/equitable interest in the property. Proof of disability required with initial application.Deadline: Can be filed anytime during the assessment year

Returning Veterans' Homestead Exemption

$5,000 reduction in assessed value for two years

Provides a $5,000 reduction in assessed value for veterans returning from active duty in an armed conflict.

Eligibility: Available for veterans who return from active duty in an armed conflict involving the armed forces of the United States and who own and occupy their residence as a primary home.Deadline: File with Chief County Assessment Office upon return

Official Resources

DeKalb County Assessment Office - Official Website →

Official county assessment office website with information on assessments, exemptions, and Board of Review procedures.

DeKalb County Board of Review - Appeal Forms and Deadlines →

Download residential and commercial appeal forms, view Board of Review rules, and check township publication deadlines for filing appeals.

Illinois Property Tax Appeal Board (PTAB) →

State-level appeal board for property owners dissatisfied with their county Board of Review decision, including forms, filing instructions, and deadlines.

DeKalb County Property Tax Inquiry System →

Search property assessments, view property record cards, and access tax information for properties in DeKalb County.

Illinois Department of Revenue - Property Tax Information →

State property tax information including exemption details, assessment procedures, and taxpayer resources for Illinois property owners.

Check Your DeKalb County Assessment

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Frequently Asked Questions

What is the deadline to appeal my property assessment in DeKalb County?

The deadline to file a property tax appeal with the DeKalb County Board of Review is 30 days from the date your township's assessments are officially published. Each township in DeKalb County publishes assessment notices at different times throughout the year, typically in spring. The publication date appears on your assessment notice. If the 30-day deadline falls on a weekend or holiday, it extends to the next business day. After this deadline passes, the Board of Review is prohibited by law from accepting assessment complaints for properties in that township for that year. To find your specific township's deadline, call (815) 895-7120 or visit the Board of Review publications page at dekalbcounty.org.

Should I contact my Township Assessor before filing a Board of Review appeal?

Yes, it is strongly recommended that you first discuss your assessment with your Township Assessor before filing a formal appeal with the Board of Review. Many times, the reason for an assessment change can be made clear through this conversation, and potential errors or misunderstandings can be resolved without needing to file an appeal. The Township Assessor can explain how they arrived at your property's value, review your property record card for accuracy, and may agree to make corrections if errors are found. This informal review can save you significant time and effort. Only if you remain unsatisfied after speaking with the Township Assessor should you proceed with filing a formal Board of Review appeal.

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

The potential savings from a successful property tax appeal in DeKalb County depends on how much your assessed value is reduced and the local tax rate applied to your property. With DeKalb County's effective tax rate averaging 2.22%, every $3,000 reduction in assessed value translates to approximately $66 in annual tax savings. For example, if you successfully reduce your assessed value from $82,334 to $72,334 (a $10,000 reduction), you would save approximately $222 per year in property taxes. Given that Illinois assesses property at 33.33% of market value, a $30,000 reduction in market value opinion would result in a $10,000 assessed value reduction. The key is providing strong evidence that your property is overvalued compared to similar properties in your neighborhood or that your assessment contains factual errors.

What evidence do I need for a successful DeKalb County property tax appeal?

To build a strong appeal in DeKalb County, you need compelling evidence that your property is over-assessed. The most effective evidence includes comparable sales data from the past 6-12 months showing similar homes in your area that sold for less than your assessed market value, or assessment equity comparables showing similar properties assessed at lower values per square foot. The Board of Review appeal form includes a grid analysis section where you should provide at least three comparable properties similar to yours in size, age, condition, and location. Additional helpful evidence includes photographs documenting property condition or defects, a professional appraisal conducted by a licensed appraiser, your property record card with any errors highlighted (such as incorrect square footage, wrong number of rooms, or features you don't have), and contractor estimates for needed repairs. The more thorough and well-organized your evidence, the better your chances of success.

Can I appeal my DeKalb County property taxes online or do I need to mail forms?

DeKalb County Board of Review does not currently accept appeals via email, fax, or online portal. You must submit your appeal either by mail or in person. For mail submissions, send one complete original appeal form with all supporting evidence to: DeKalb County Board of Review, Administration Building, 110 E Sycamore St., 4th Floor, Sycamore, IL 60178. Your envelope must be postmarked by the filing deadline date. For in-person submissions, deliver your completed appeal during business hours (8:30 AM to 4:30 PM, Monday through Friday) to the same address by the deadline date. Make sure to keep copies of everything you submit for your records. The county's website at dekalbcounty.org provides downloadable appeal forms, but the actual filing must be done via mail or in person.

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

After you file your appeal, the Board of Review will process your complaint and schedule a hearing based on your preference indicated on the appeal form (waive oral hearing, teleconference, in-person, or virtual). You will receive notice of your hearing date and time, and hearings set by the Board will not be rescheduled. At the hearing, you will present your evidence supporting your requested assessed value, and the Township Assessor will present evidence supporting the current assessment. Both parties typically have a set amount of time to present their cases. The Board of Review members will consider all evidence presented and issue a written decision either confirming, reducing, or potentially increasing your assessed value. You will receive a Notice of Final Decision by mail. If you disagree with the Board's decision, you have 30 days from the date of that notice to file an appeal with the Illinois Property Tax Appeal Board (PTAB).

What is the homestead exemption worth in DeKalb County?

The General Homestead Exemption in DeKalb County reduces your property's equalized assessed value by up to $6,000. With DeKalb County's average effective tax rate of 2.22%, this exemption saves eligible homeowners approximately $133 per year in property taxes. To qualify, you must own and occupy the property as your primary residence as of January 1 of the tax year. This is a one-time application that does not require annual renewal unless ownership changes. Additional exemptions may be available if you're a senior citizen (up to $5,000 additional reduction for those 65+), disabled veteran (ranging from $2,500 to full exemption depending on disability rating), or disabled person ($2,000 reduction). These exemptions can be stacked, meaning a qualified senior homeowner could receive both the $6,000 general homestead exemption and the $5,000 senior exemption for a total $11,000 reduction in assessed value. Applications can be filed anytime during the assessment year at the Chief County Assessment Office.

Can I appeal to the Illinois Property Tax Appeal Board if I lose at the Board of Review?

Yes, if you are dissatisfied with the DeKalb County Board of Review's decision, you have the right to appeal to the Illinois Property Tax Appeal Board (PTAB). You must file your PTAB petition within 30 days of the postmark date on the Board of Review's written Notice of Final Decision. The PTAB is a state-level quasi-judicial body that provides an independent review of your property's assessment. You must use PTAB's official petition forms available at ptab.illinois.gov or by calling (217) 782-6076. The PTAB appeal requires you to submit evidence supporting your claim, and the Board of Review will also submit evidence defending their decision. Individual homeowners may represent themselves before PTAB, though corporations and LLCs must be represented by an attorney licensed in Illinois. PTAB decisions can take several months, and if you remain unsatisfied with their decision, you can seek judicial review in circuit court under the Administrative Review Law.

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 →

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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/ | https://www.tax-rates.org/illinois/dekalb_county_property_tax | https://www.ptab.illinois.gov/ | https://tax.illinois.gov/localgovernments/property/taxrelief.html | https://www.zillow.com/home-values/55433/dekalb-il/ | https://www.redfin.com/city/4949/IL/DeKalb/housing-market

Last verified: 2026-03-05