65 ILCS 5/3.1-35-45
At the end of every month, and oftener if required by the corporate authorities, the municipal treasurer shall render an account under oath to the corporate authorities, or to an officer designated by ordinance, showing the state of the treasury at the date of the account and the balance of money in the treasury. The treasurer shall accompany the account with a statement of all money received into the treasury and on what account, together with all warrants redeemed and paid by the treasurer. On the day the treasurer renders an account, these warrants, with all vouchers held by the treasurer, shall be delivered to the municipal clerk and filed, together with the account, in the clerk's office. All paid warrants shall be marked "paid". The treasurer shall keep a register of all warrants, which shall describe each warrant, showing its date, amount, and number, the fund from which paid, the name of the person to whom paid, and when paid.
65 ILCS 5/3.1-35-45