What Is Stacking Insurance

Stacking insurance generally refers to combining uninsured motorist (UM) or underinsured motorist (UIM) coverage limits from more than one insured vehicle or policy when state law and the policy permit it. In Pennsylvania, stacking can significantly increase the amount of UM/UIM protection available after a crash caused by a driver who has no insurance or insufficient liability coverage. For example, if a household has three vehicles with $100,000 of stackable UIM coverage on each, the potentially available stacked limit may be $300,000, subject to the policy terms and applicable law. Pennsylvania insurers may allow an insured to waive stacking, and a valid waiver can affect the coverage available after an accident. Questions can also arise about stacking coverage across separate policies. Because UM/UIM policy language, waivers, household vehicles and the identity of the injured person all matter, coverage should be reviewed carefully after a serious accident. The declarations page alone may not answer every stacking question.