The "100/300" in "100/300 auto insurance" refers to the bodily injury liability limits (in thousands) of a policy. The 100 means that the policy will cover up to $100,000 of bodily injury sustained by a single person injured in an accident, and the 300 means that it will cover up to $300,000 total for bodily injury per accident.

Generally, 100/300 will be followed by a third number, such as 50, and together will look like 100/300/50. What the 50 represents is the amount of property damage liability coverage, in thousands, that the insurance policy includes. In this example, the policy will also pay for up to $50,000 for the repair of other people's property.

Let’s take another example. If a policy covered $50,000 of bodily injury sustained by a single person injured in an accident, $100,000 total for bodily injury per accident, and $50,000 for damage to other people’s property, this would be a 50/100/50 policy. That means the difference between our two examples (50/100 vs 100/300 insurance) is both one of coverage per person and coverage per accident.

Remember, liability coverage compensates other people for their accident-related damages that someone insured under your policy is responsible for. It doesn't pay for the injuries of anyone covered under your policy.

Auto insurance policies with limits that are as high as 100/300 are often purchased either voluntarily or because they are required by a finance company.

State laws setting minimum liability limits don't usually require such high limits unless there are special circumstances. The states with the highest liability coverage requirements are Alaska and Maine, which require 50/100/25 coverage.

However, there are instances where a state may make you carry 100/300. In Florida, drivers who have been convicted of driving under the influence of drugs or alcohol must maintain liability limits of 100/300/50.

A more common reason for purchasing 100/300/50 coverage is the policyholder is leasing a vehicle and the finance company is requiring them to carry these limits as part of the lease agreement. Leasing companies require this amount of coverage to make sure that you're somewhat protected financially in the event you're found responsible for causing injuries or damages in "their" vehicle.

Consider Higher Limits Voluntarily

Drivers may want to think about getting more insurance protection even when they're not required. Most states don't require much coverage when compared with what an accident could potentially cost. A number of states make drivers carry 25/50 bodily injury limits, which can easily be used up following a serious accident. It's often suggested that drivers carry 100/300/50. You can still find a cheap policy with coverage at this level, and having the extra protection could go a long way.