DuPage County deadline tracker

DuPage County 2026 assessment appeal deadlines

In DuPage County, you don't get one countywide deadline. Each township publishes its assessment list in a local newspaper, then you generally have about 30 days to file with the Board of Review. City limits are not township lines — check your parcel.

How to use this tracker Find your township → note its status → if open, run a free estimate; if TBD, get an alert; if closed, review next-step options.
Open — You can still file for 2026. TBD — The assessment list is not published yet. Closed — The 2026 Board of Review window ended.

Verified against DuPage County sources: September 28, 2026. Statuses use America/Chicago time.

Open for 2026 filing

1 township
Open

Bloomingdale Township

Deadline: October 26, 2026

7 days left. Published September 25, 2026 in the Addison Suburban Life; Carol Stream Suburban Life.

Check my property

Publication date still TBD

4 townships
TBD

Winfield Township

Not published yet. The 2026 filing deadline has not been posted.

You can prepare now, but confirm the official publication before treating the window as open.

TBD

Milton Township

Not published yet. The 2026 filing deadline has not been posted.

You can prepare now, but confirm the official publication before treating the window as open.

TBD

Lisle Township

Not published yet. The 2026 filing deadline has not been posted.

You can prepare now, but confirm the official publication before treating the window as open.

TBD

Downers Grove Township

Not published yet. The 2026 filing deadline has not been posted.

You can prepare now, but confirm the official publication before treating the window as open.

2026 filing window closed

4 townships
Closed

Wayne Township

2026 window closed: September 28, 2026

Review record corrections, exemptions, and preparation for the next filing cycle.

See options if you missed the window
Closed

Addison Township

2026 window closed: October 13, 2026

Review record corrections, exemptions, and preparation for the next filing cycle.

See options if you missed the window
Closed

Naperville Township

2026 window closed: October 13, 2026

Review record corrections, exemptions, and preparation for the next filing cycle.

See options if you missed the window

Deadline alerts

Get an email when a TBD township publishes

Choose one or more townships. We'll store your email and selections so a publication alert can be sent when the county posts the dates.

Official DuPage County sources

DuPage County assessment complaint deadlines are tied to township assessment publication dates. DuPage routes townships by parcel number prefix; city limits and township boundaries are not the same.

Disclaimer: HomeTaxChallenge is not a government agency and is not affiliated with the DuPage County Assessment Office or DuPage County Board of Review. Always confirm dates on the official county sources above. This is not legal, tax, or appraisal advice.