In indemnity policies, the upper limit of a claim is the sum assured and this usually applies for the period of the policy. Certain policies, however, allow for reinstatement of the Sum Insured by payment of proportionate premium for the remaining period of the policy. The actual claim will be the actual extent of financial loss as validated by documents like bills. If the property is underinsured, the insured shall bear a rateable proportion of the loss. There can be more than one claim in the policy period but the sum assured is usually the limit for the policy period unless reinstated.
Nowadays health insurance policies – which cover hospitalisation costs – have also a cashless settlement of claims. That is, you don’t have to pay for the treatment at the hospital and then make a claim for reimbursement of the expenses. The insurance company has a service provider called the third party administrator (TPA) health services, who liaises with the hospitals and directly makes the payment for your treatment as per the terms of your policy and coverage.