• Aggregate is (1) a limit on an insurance policy that provides for a maximum payout for all covered losses incurred over a specified period of time, usually a year. Cumulative limits are usually included in the liability policy. While aggregates are not often used in property insurance, they are sometimes included for certain catastrophic risks such as earthquakes and floods. (2) The amount of reinsurance coverage in US dollars for one specified period, usually 12 months, for all reinsurance losses incurred under the contract during such period.