Montana Title 33. Insurance and Insurance Companies § 33-22-924. Renewal requirement

(1) If a person pays a renewal premium on the date it is due or within 31 days after it is due, an insurer may not refuse to renew a medicare supplement policy or certificate unless the insurer:

(2) If an insurer refuses to renew all policies or certificates in this state that are of the same form and issued to persons of the same class, the policies or certificates will remain in force during the grace period stated in the replaced policy or certificate. An insurer's refusal to renew a policy or certificate may not affect a claim that arose under the discontinued policy or certificate during the period in which an insured was confined without interruption to a medical care facility for treatment.