Umbrella coverage is used to help protect from catastrophic losses. Umbrellas generally sit over an underlying liability policy and increases the limits by the amount of the umbrella.

For example if you have a commercial auto policy with a limit of $1,000,000 but want to have a limit of $2,000,000, this can be done by purchasing a $1,000,000 umbrella policy. Your underlying carrier will be the first $1,000,000 and after that the umbrella Carrier would then pick up cost above $1,000,000 up to the umbrella limit.