Tertiary Insurance Definition

Tertiary insurance is a third policy. When you have multiple insurance policies, such as if you have Medicare and a supplemental policy, it's possible to have more than one covering a given procedure or loss. The third one to be billed is referred to as tertiary coverage. Stacking policies can be helpful in that one may cover an expense that the other one doesn't while a third one may pay your deductible or copay for you.

Multiple Health Policies

It's not uncommon for families to have multiple health policies, leading to situations with tertiary insurance. For instance, a college student with divorced parents may have coverage from each parent and an additional, tertiary, policy offered through his college. Some families with coverage may also qualify for a state-administered Children's Health Insurance Program in addition to their private coverage.

Supplementary Health Coverage

Tertiary supplementary policies work hand-in-hand with existing health insurance. For instance, you may have an existing high-deductible health insurance policy that pays for your surgery and a secondary policy that helps to defray your deductible. A tertiary supplementary policy can help to pay your other out-of-pocket costs. If you have two health insurance policies, like in a situation where both you and your spouse are covered by your own policies, any additional insurance would technically be tertiary.

Medicare Gaps

Medicare is actually set up to work with tertiary policies. Given that there are areas Medicare doesn't cover, many senior citizens choose to purchase secondary Medigap policies that protect them further. Any coverage in addition to Medigap would be tertiary. This could include a supplemental policy for out-of-pocket costs, a travel policy for coverage when abroad or insurance through a family member or employer.

Other Types of Insurance

Health insurance isn't the only area where you can end up with tertiary coverage. Rental cars could be covered by your auto insurance policy, your credit card's policy and any insurance through the rental car agency. Credit card purchase protection can also be a third line of insurance, working with your primary renters or homeowners insurance and with any additional riders or separate policies you buy. Travel insurance may also be tertiary for you.