A health insurance policy that allows an insurer to change the policy owner's premiums, but NOT cancel the policy is called a(n):

A policy that allows the insurer to change the policy owner's premiums but prohibits the cancellation of the policy is known as a guaranteed renewal policy. This type of policy is designed to ensure that the policyholder can continue their coverage as long as they pay the required premiums, even if their health status changes. The insurer retains the right to adjust the premiums, typically based on overall group risk or inflation, but they cannot cancel the policy as long as the premiums are paid.

This feature provides a level of security for the insured, as they will not face the risk of losing coverage due to health issues that arise during the policy term. It differs from other policy types, such as non-cancelable policies, which fix both the premiums and the coverage without any possibility of rate increases, or guaranteed issue policies, which guarantee acceptance without regard to health status but may have different renewal provisions. Thus, the guaranteed renewal policy strikes a balance by allowing premium increases while still protecting the insured's right to ongoing coverage.