Stacked vs. Unstacked Car Insurance

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In most cases, your car insurance policy has strict limits that apply to each portion of your coverage. Once you’ve exhausted those limits, your insurance company won’t pay out any more to cover your damages. But in the case of uninsured motorist coverage, some states permit drivers to “stack” coverage limits for multiple vehicles or policies, resulting in a much higher coverage limit. Bankrate’s insurance editorial team reviews the ins and outs of stacked vs. unstacked auto insurance to help you make an informed decision about your coverage.

What is stacked car insurance?

Stacked insurance means increasing your uninsured and underinsured motorist coverage by combining (or stacking) the limits on each vehicle you own. If you do this, you’ll get a greater amount of financial protection if you get into an accident with a driver who only has your state’s minimum liability coverage (or none at all). However, it’s vital to note that these coverage increases only apply to the bodily injury portion of your policy and not to property damage. For example, if an uninsured motorist hits your vehicle, damaging it and injuring you, your increased coverage from stacking would not pay towards repairing your vehicle, but could help with your medical expenses.

There are two ways to stack your protection. If all your cars are insured on a single policy, uninsured/underinsured motorist coverage can be stacked “vertically” — that is, within the same policy. If your cars are insured under separate policies with the same carrier, the stacked coverage would be considered “horizontal”. Be aware, though, that just because a state allows it does not mean your car insurance carrier will offer policy stacking, vertical or horizontal.

Stacked car insurance on one policy

To effectively stack car insurance within one policy — vertical stacking — you would need to have at least two vehicles on the same policy. For example, let’s say the policy has $25,000 per accident for uninsured motorist bodily injury protection. If you stack your coverage and are insuring two vehicles on your policy, your uninsured motorist bodily injury coverage would extend up to $50,000 per accident. If you had three vehicles on your policy, it would be up to $75,000 for this coverage per accident.

A way to remember stacking in this scenario is that stacking is your uninsured/underinsured motorist coverage limit multiplied by the number of vehicles on your policy. This calculated amount would generally be your new, stacked coverage limit.

Stacked car insurance on multiple policies

Some states also allow horizontal stacking of uninsured and underinsured motorist protection for vehicles that are on different policies, but within the same household and your name is listed on each policy. For example, suppose you have $25,000 in uninsured motorist coverage, and your child also has the same amount of coverage. In that case, you may be able to have $50,000 worth of coverage after an accident involving an uninsured driver who is found at fault. In some states, this is the only way to stack uninsured/underinsured motorist coverage.

Pros and cons of stacked car insurance

What is unstacked car insurance?

Unstacked car insurance is the opposite of stacked car insurance — meaning your uninsured and underinsured motorist coverage limits are not combined, even if you insure multiple vehicles or live with another driver who insures their vehicle. If your car insurance is unstacked, then you would receive up to the uninsured and underinsured coverage limits listed on your policy’s declarations page. 

If you live in one of the states below, unstacked car insurance is the only option available to you: 

• Alaska
• Arizona
• California
• Connecticut
• Idaho
• Illinois
• Iowa
• Kansas
• Lousiana
• Maine
• Maryland
• Massachusetts
• Michigan
• Minnesota
• Nebraska
• North Dakota
• South Dakota
• Washington

Pros and cons of unstacked car insurance

What states allow car insurance stacking?

Not all states allow stacking, and some may only allow multiple-policy stacking. If your state has a high number of uninsured motorists, it may be worth your while to consider stacking your coverage if possible. This could be especially important if you or any of your frequent passengers don’t have their own health insurance. If your state allows stacked coverage, but your current carrier doesn’t, you could consider switching car insurance carriers to one that offers stacked policies. You may want to speak with your agent to get a quote and see if stacked coverage makes sense for your policy.

• States that allow both single policy and multiple policy stacking
  

  Alabama
  Arkansas
  Colorado
  Florida
  Hawaii
  Indiana
  Kentucky
  Mississippi
  Missouri
  Montana
  Nevada
  New Hampshire
  New Mexico
  Ohio
  Pennsylvania
  Rhode Island
  South Carolina
  Vermont
  Virginia
  West Virginia
  Wisconsin
  Wyoming

• States that only allow multiple policy stacking
  

  Delaware
  Georgia
  New Jersey
  New York
  North Carolina
  Oklahoma
  Oregon
  Tennessee
  Texas
  Utah

Is stacked insurance worth it?

Some may think that more coverage is always better, but it depends on what is important to you as a driver and what fits your budget as a policyholder. Stacked insurance typically comes with a higher premium, which may not make the added financial protection worth it for some drivers. If you’re grappling with the decision between stacked and unstacked insurance, here are some factors to review with your agent:

• Do you have health insurance that you are comfortable using? Your health insurance typically pays for medical bills resulting from a car accident once the uninsured motorist coverage from your insurance policy is exhausted. Drivers with high-deductible health insurance plans may save money by paying for stacked coverage instead.
• Do you frequently have passengers in your vehicle? Uninsured motorist coverage also pays for your passengers’ medical bills. If you regularly have passengers in your car, stacked insurance is a way to help safeguard them from having to use their insurance in the event of an accident.
• Does having stacked insurance drastically increase your premium? Depending on your insurance company, the number of vehicles on your policy, driving history and other factors, stacking insurance may slightly raise your premium. Or it could cause a drastic rate hike. Again, it’s a good idea to talk with your insurance agent to see if the numbers make sense for you.
• Does your policy have personal injury protection(PIP) or medical payments coverage? PIP and medical payments coverage are used as primary coverage—they pay out first at the time of a covered loss. Other insurance coverage on your policy will pay out as secondary coverage, so evaluating your other coverage limits can help you decide.

Frequently asked questions

• Can I update my car insurance to be stacked?
  

  If you live in a state that permits stacked car insurance and you own multiple vehicles, you may be able to stack your insurance by speaking with your insurance company. If your carrier does not offer stacked coverage, it may be necessary to consider other local carriers. Keep in mind that stacked insurance can come with a higher premium, so be prepared to weigh the pros and cons of making this update.

• What is the average cost of stacked vs. unstacked car insurance?
  

  The average cost of car insurance varies and is based on many factors, and stacking can add a little or a lot to your insurance premium. Ideally, you will want to balance the amount of insurance you feel you need with a price that fits within your budget. Getting a quote and speaking with your agent will help you narrow down your options.

• What other car insurance coverage is stackable?
  

  Uninsured and underinsured motorist coverage is the only stackable car insurance coverage, and specifically only for bodily injury and not property damage. If you need higher limits on other insurance coverage, consider asking your agent to provide quotes at higher policy levels. Also, you can usually increase your policy limits online or through your provider’s app to see the premium difference in real time.

• What does rejecting stacked auto insurance mean?
  

  Some states require policyholders to reject uninsured and underinsured motorist policy coverage in writing or by completing an electronic rejection form. For car insurance companies that allow stacked vs. unstacked uninsured motorist coverage, this form also allows policyholders to accept uninsured motorist coverage but reject stacking the coverage to save on premiums.