Grundy County deadline

Grundy County 2026 assessment complaint deadline

The 2026 county-wide complaint window is open through October 26, 2026.

County-wide model Grundy County used one complaint window for the whole county in 2026; this is not a township-by-township publication calendar.

2026 Board of Review complaint window

Open

Grundy County county-wide

Opened: September 23, 2026

Deadline: October 26, 2026

23 days remain. Confirm the filing method on the official Board of Review site.

Official Grundy County sources

Grundy County states that 2026 assessment notices were mailed on September 23, 2026 and published in the Coal City Courant and Morris Herald-News. The county lists Monday, October 26, 2026 as the assessment complaint deadline: in-person complaints must be received by 4:30 pm, email submissions to bor@grundycountyil.gov must include the complete signed complaint form and all evidence by 11:59 pm, and mailed complaints must be postmarked by 11:59 pm.

Disclaimer: HomeTaxChallenge is not a government agency and is not affiliated with the Grundy County Assessment Office or Grundy County Board of Review. Always confirm dates and filing instructions on the official county sources above.