10 ILCS 5/19A-50: Receipt of ballots.

Upon receipt of the voter's ballot, the election judge or official shall enclose the unopened ballot in a large or carrier envelope that shall be securely sealed and endorsed with the name and official title of the election judge or official and the words, "This envelope contains a ballot and must be opened on election day", together with the number and description of the precinct in which the ballot is to be voted, and the election authority shall safely keep the envelope in its office until delivered to the central ballot counting location. The ballots determined to be valid shall be added to the vote totals for the precincts for which they were cast in the order in which the ballots were opened.