What type of disability income plan does not allow the insurer to change or alter premium rates?

A noncancellable disability income plan is designed in such a way that the insurer cannot change the premium rates or terms as long as the policyholder continues to pay the premiums. This offers a significant advantage for the insured because it provides certainty regarding future premium costs, regardless of changes in the insured's health or in the insurer’s underwriting criteria. By locking in the premium rate, it protects policyholders from potential rate increases that may occur in renewable or other forms of policies.

On the other hand, while renewable plans allow policyholders to renew coverage without health re-evaluation, they do not guarantee that premiums will remain the same; these could be altered at the insurer's discretion. Guaranteed plans generally imply that specific benefits or coverage levels are promised, but do not necessarily mean that premium rates are fixed. In a semi-cancellable plan, the insurer may have some ability to adjust premiums after a specified period or under certain conditions. Hence, noncancellable plans stand out for their strong consumer protection by ensuring both fixed premium rates and coverage terms.