A McHenry County owner files a formal 2026 assessment complaint with the McHenry County Board of Review during the 30-day period opened by publication of the property's township assessment roll. The county requires electronic submission through its complaint portal and states that a complaint form and the appropriate assessment grid are both required. The owner may first discuss the record and valuation with the township assessor, but that conversation is not a filed complaint. FairPath can provide a guided manual workflow for checking the notice, collecting owner-selected comparisons, labeling photographs, and organizing a submission checklist. FairPath does not calculate an official McHenry assessment, upload the complaint, represent the taxpayer, or promise that a filing will be accepted.
Assessment context: McHenry County assessment administration is divided among township assessors, the county Office of Assessments, and the county Board of Review. Township assessors maintain local property facts and values; the county publishes notices, monitors equalization, and supports the Board; the Board hears formal complaints. Starting in 2026, the county says assessment notices will be posted online, while mailed notices continue for revaluations, farmland, and new properties. Properties adjusted only by an equalization factor may not receive a paper notice. That makes the official property-tax inquiry portal and alert service important. An assessment complaint concerns overvaluation, inequity, or another supported assessment issue, not simply the amount of the tax bill or the absence of a mailed notice.
Filing process: Identify the township and retrieve the 2026 assessment notice from the McHenry County Property Tax Inquiry system. Then consult the county's Township Filing Deadlines page because each township receives its own publication and closing dates. Download the current form and the grid that matches the property type, complete and save them, and upload both through Submit Your Complaint before midnight on the listed date. The filing page says complaints can only be submitted through that portal and will not be accepted by email. Include an email address to receive a copy, keep the on-screen submission message, and use the county complaint lookup after the stated processing interval to verify receipt. A portal upload without the required form and grid is not a complete complaint.
Evidence to review: McHenry's filing instructions treat the complaint grid as required, not optional background. Build the argument around the chosen basis. For overvaluation, compare credible market evidence and explain why selected sales reflect the subject's location, size, age, style, quality, amenities, and condition. For inequity, compare current assessments of genuinely similar properties using a consistent measure. The county specifically instructs filers to label every evidence photograph with the PIN or address so the Board can identify the image. Dated condition photographs, a property record, measurements, permits, contractor information, or other documents can support a factual difference when tied to the requested correction. Confirm that every uploaded file appears in the county complaint lookup; the 2026 rules place responsibility on taxpayers to confirm that the county received their complaint and evidence.
Current deadline guidance: Township-specific 30-day window; current 2026 dates are posted as each roll publishes. A McHenry County Board of Review complaint must be filed within 30 days after the current assessment is published in the newspaper for the property's township. Publication is staggered. As reviewed July 15, 2026, the county listed Richmond Township as published July 7 with an August 6 deadline and Chemung Township as published July 14 with an August 13 deadline; the remaining township dates were not yet posted. These examples do not control another township. Check the official 2026 Township Filing Deadlines page and the online assessment notice before filing. Late complaints are not accepted.
McHenry County's 2026 publication sequence was active when reviewed. Richmond Township published July 7 and closed August 6; Chemung published July 14 and closed August 13. Other townships remained blank on the county deadline table. Owners in Algonquin, Dorr, Grafton, McHenry, Nunda, or another township must wait for and use that township's own publication information.
Online notices are a material 2026 process change. A property receiving only an equalization-factor adjustment may not receive a mailed notice, while notices for revaluations, farmland, and new property continue by mail. Search the official inquiry portal with the correct tax year and sign up for county alerts instead of assuming that no envelope means no review window.
The county requires both a complaint form and a corresponding grid. The form page warns that merely uploading general evidence does not replace those documents. Choose the residential, commercial, or industrial materials that match the subject, complete all required fields, and retain the exact uploaded versions with the portal receipt.
Photograph identification is an explicit county instruction. Put the subject or comparable PIN or address on each photo page and explain what the image demonstrates. Unlabeled pictures of repairs or exterior differences can be difficult to associate with a parcel and should not be treated as self-explanatory evidence.
Official filing authority: McHenry County Board of Review. https://www.mchenrycountyil.gov/departments/assessments/submit-your-complaint
Source: McHenry County Office of Assessments, 2026 Township Filing Deadlines, https://www.mchenrycountyil.gov/departments/assessments/board-of-review/township-filing-deadlines. Reviewed 2026-07-15.
Source: McHenry County Board of Review, Submit Your Complaint, https://www.mchenrycountyil.gov/departments/assessments/submit-your-complaint. Reviewed 2026-07-15.
Source: McHenry County Office of Assessments, Filing a Complaint, https://www.mchenrycountyil.gov/departments/assessments/filing-a-complaint. Reviewed 2026-07-15.
Source: McHenry County Board of Review, 2026 Board of Review Rules, https://www.mchenrycountyil.gov/home/showpublisheddocument/122520/639185026958230000. Reviewed 2026-07-15.
Source: McHenry County Office of Assessments, Assessment Notice Information, https://www.mchenrycountyil.gov/departments/assessments/assessment-notice-information. Reviewed 2026-07-15.