Effective January 1, the U.S. Postal Service changed how it defines a postmark. Previously, a postmark reflected the date mail was received by USPS. Under the new policy, a postmark now reflects the date the mail is processed, which may occur days after a voter drops their ballot in the mail.
As a result, mail ballots placed in blue USPS collection boxes or dropped in post office mailboxes may not be postmarked the same day. This processing delay could affect whether a ballot meets Illinois’ legal requirements to be counted — even when voters follow all existing rules.
To help prevent eligible ballots from being disqualified, the Cook County Clerk’s Office is strongly encouraging vote-by-mail voters to take one of the following steps:
- Bring their ballot directly to a USPS retail location and request it be postmarked at the counter; or
- Use one of the 55 secure mail ballot drop boxes that will be available throughout suburban Cook County beginning March 2, 2026.
View Cook County Clerk's Office Informational Flyer - English
View Cook County Clerk's Office Informational Flyer - Spanish
Watch this Brief Video on the New Changes