The cost of Umbrella insurance in Massachusetts varies based on two essential factors – Your insurance limit and risk exposure. You can buy Umbrella liability policies in increments of $1 million. The higher the limits, the higher the coverage costs. Similarly, insurance companies evaluate risk exposure based on the number of properties and vehicles/watercraft, driving record, occupation, and age, among other factors. The higher your risks, the higher the coverage costs. On average, Bay Staters can expect a $1 million policy to cost around $160 to $500.