Definition - What does Primary Insurance mean?
Primary insurance is a policy that pays for coverage first, even when the policyholder has other policies that cover the same risk. Those other policies will only be tapped when the primary policy has reached its financial limit.
Insuranceopedia explains Primary Insurance
Primary policies are usually relevant to property, liability, or health coverage.
The first policy to pay the financial loss is the primary insurance. Secondary or excess insurance pays for the amount that remains when the primary policy's coverage has been exhausted.
For instance, some people in the US have health insurance besides Medicare. When they bill for a medical expense that is insurance-dependent, the non-Medicare insurance is charged first. Medicare pays only for the excess amount.