For month-to-month leases (see the Illinois rental agreement for tenancies at will) most states will require at least a 30 Day Notice to Vacate. Landlords or tenants in Illinois can use this form to communicate the date by which the rental property should be empty. The Illinois Notice to Vacate Form is an easy way to end your Illinois rental lease. Illinois Notice to Vacate - Why is it important? Many Illinois property management companies also ask their tenants to provide a Notice to Vacate at least 30, 60, or 90 days before the lease has expired if they plan to move out at the end of the term. This Illinois Notice to Vacate Form notifies tenants to vacate the rental property, remove their possessions and return the keys by the expiration of the term. Illinois Notice to Vacate Forms are used by landlords and tenants in Illinois to notify the other party that they do not intend to renew their rental agreement.