(4) For the purpose of this Code the term "underinsured motor vehicle" means a motor vehicle whose ownership, maintenance or use has resulted in bodily injury or death of the insured, as defined in the policy, and for which the sum of the limits of liability under all bodily injury liability insurance policies or under bonds or other security required to be maintained under Illinois law applicable to the driver or to the person or organization legally responsible for such vehicle and applicable to the vehicle, is less than the limits for underinsured coverage provided the insured as defined in the policy at the time of the crash . The limits of liability for an insurer providing underinsured motorist coverage shall be the limits of such coverage, less those amounts actually recovered under the applicable bodily injury insurance policies, bonds or other security maintained on the underinsured motor vehicle. On or after July 1, 1983, no policy insuring against loss resulting from liability imposed by law for bodily injury or death suffered by any person arising out of the ownership, maintenance or use of a motor vehicle shall be renewed or delivered or issued for delivery in this State with respect to any motor vehicle designed for use on public highways and required to be registered in this State unless underinsured motorist coverage is included in such policy in an amount equal to the total amount of uninsured motorist coverage provided in that policy where such uninsured motorist coverage exceeds the limits set forth in Section 7-203 of the Illinois Vehicle Code.
The changes made to this subsection (4) by this amendatory Act of the 93rd General Assembly apply to policies issued or renewed on or after December 1, 2004.