A disability contract that has a set premium rate that cannot change is called a

Expense arrangement contracts typically involve agreements centered around the reimbursement of specific expenses incurred, rather than the stability of premium rates. These contracts do not inherently guarantee fixed premiums; rather, they may be subject to change based on the costs associated with the covered expenses.

While guaranteed renewable contracts allow policyholders to renew their policy at the end of each term without evidence of insurability, they do not assure that premium rates will remain unchanged. Insurers can adjust premiums based on the insured's age or other factors at renewal, which distinguishes them from noncancelable contracts.

Continuous indemnity contracts refer to policies that provide ongoing benefits for a disability until a specified event occurs, such as recovery or reaching a certain age. They do not specifically relate to the immutability of premium rates, meaning that premiums can be subject to change depending on the insurer's policies.