Do I Get Coverage From All My Insurance Policies On All My Vehicles?

Many people own more than one vehicle, and so have purchased more than one insurance policy.  By way of example, assume you own two vehicles, each with an insurance policy and for which you have paid a separate premium.  Do the coverages add together or “stack”?

The question of whether multiple automobile insurance policies will “stack” or provide additive coverage has been the subject of legislation and litigation in Missouri for many years.  The short answer is that all policies are different, and all forms of insurance are different -- resulting in a wide variety of answers.

Liability Insurance -- As a general rule (there are exceptions), the Liability insurance coverages you purchased if you own multiple vehicles are not likely to stack.  The public policy of Missouri, as set by the legislature, has never been interpreted to require stacking of Liability insurance.

The general rule has long been that, since each vehicle requires its own Liability policy in order to be legally driven, the Liability insurance applies to each vehicle alone, and does not stack.  The so-called “anti-stacking” language in most Liability insurance policies generally has been held to prevent stacking of Liability insurance.

That said, another general rule is that where an insurance policy contains ambiguous language, such that the purchaser of the policy might think they bought stacked coverage, then the ambiguity is always resolved in favor of the purchaser.  The Courts have been consistent in resolving ambiguities in favor of extending coverages -- and on occasion permitting Liability insurance to stack under unique factual situations.

So, while Liability insurance is not likely to stack, it does happen from time-to-time under unique facts and ambiguous policy language.

Uninsured Motorist -- Unlike Liability coverage, the public policy of Missouri as set by the legislature has generally been interpreted by the Courts to require stacking of Uninsured Motorist coverage.  Like Liability insurance, Uninsured Motorist insurance is mandatory, and is required by statute.

Unlike Liability insurance which applies to ownership, use, or maintenance of a motor vehicle, Uninsured Motorist insurance is “personal” and will follow you to provide protection even when you are not using a motor vehicle.  For example, if you are a pedestrian and are struck by a motorist with no Liability insurance, your own Uninsured Motorist policy will provide coverage -- even though you were not using your vehicle.

For that reason, the general rule is that Uninsured Motorist coverage stacks because you pay a separate premium for each policy for “personal” insurance.

Some insurance companies have tried to avoid stacking by selling individual Liability insurance policies, and then selling a single Uninsured Motorist policy applicable to all vehicles you own.   The Courts have consistently struck down this practice because each Liability policy is statutorily required to have its own Uninsured Motorist policy.

Underinsured Motorist -- Underinsured Motorist coverage is not statutorily required, and so “anti-stacking” language in an Underinsured Motorist policy may well be upheld.  Again, the general rule has been that any ambiguous language in the policy will be resolved in favor of extending coverage for the purchaser. companies sometimes group Uninsured Motorist and Underinsured Motorist coverages together in a single coverage.  When this happens, the policy most often simply defines an Uninsured Motorist and an Underinsured Motorist as both falling under the same set of definitions -- sometimes including within the definition of Uninsured Motorist any driver who carries some insurance but not enough to pay all the damages they cause.

When that happens -- grouping Underinsured Motorist insurance under the same coverage as Uninsured Motorist coverage -- the Courts have consistently applied the Uninsured Motorist public policy and “stacked” the Underinsured Motorist coverages.

Umbrella -- An Umbrella policy, whether it is limited to Liability insurance only, or includes endorsements adding Uninsured or Underinsured Motorist coverages, is not a statutorily required form of insurance, and is considered an “excess” coverage that by definition is added to your underlying base coverage.

For example, if you have a $100,000 Underinsured Motorist coverage, and a $1,000,000 Umbrella policy with an Underinsured Motorist endorsement, then in total you will have up to $1,000,000 in Underinsured Motorist coverage.  The first $100,000 in Underinsured Motorist payments will come from your base UIM policy, and the remainder (up to the policy limits of $1,000,000) will come from the endorsement to your Umbrella policy.

Because it is excess coverage, the Umbrella policy most likely will get a “credit” for the underlying base coverage, and the Umbrella coverage is not triggered until the underlying base coverage is exceeded or exhausted.

But if you have two base Uninsured Motorist policies of $100,000 each, and a $1,000,000 Umbrella policy with an Uninsured Motorist endorsement, you are not likely going to be able to “stack” the Umbrella twice.  Instead, your two base UM policies will stack to a total of $200,000, and your Umbrella (if triggered) would provide an additional $800,000 in coverage up to the $1,000,000 total.


Summary -- The details of how stacking (or anti-stacking) works in Liability, Uninsured Motorist, Underinsured Motorist, or Umbrella details that change from policy to policy and insurance carrier to insurance carrier.   Policies and coverages are all written differently by each carrier, and the details differ.  You should have an experienced personal injury and insurance attorney review all your automobile policies in advance, and advise you on how to best protect yourself in the event you are in a collision.


By: Joseph W. Rigler


DID YOU KNOW ? is presented by Williams, Robinson, Rigler & Buschjost, PC as a public information service only.  None of the information contained herein is intended to be taken as legal advice.  Each matter depends on unique facts which attorneys must consider in forming an opinion, and may depend on laws unique to a particular jurisdiction.  No two cases are the same.  If you want to know more about this subject, contact Williams, Robinson, Rigler & Buschjost, PC, or the attorney of your choice, and seek a formal opinion about your particular case.

Williams, Robinson, Rigler & Buschjost, PC provides legal services in South-Central Missouri, serving Maries County (including Belle, Vienna & Vichy), Crawford County (including Cuba, Steelville, Bourbon), Dent County (including Salem, Lecoma, Bunker), Phelps County (including Rolla, St. James, Newburg, Doolittle, Edgar Springs), Texas County (including Licking, Houston, Raymondville, Summersville, Cabool), Pulaski County (Waynesville, St. Robert, Richland, Dixon, Crocker) and may provide legal service in other locations on request.

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