Colorado Revised Statutes Title 10. Insurance § 10-4-604. Nonrenewal

(1) No insurer shall refuse to renew a policy unless such insurer or its agent mails or delivers to the named insured, at the address shown in the policy, at least thirty days' advance notice of its intention not to renew. This section shall not apply:

(2) Notwithstanding the failure of an insurer to comply with this section, the policy shall terminate on the effective date of any other insurance policy with respect to any automobile designated in both policies.

(3) Renewal of a policy shall not constitute a waiver or estoppel with respect to grounds for cancellation which existed before the effective date of such renewal.

(4) In the event an insurer refuses to renew, the insured may, by written request, demand a written notification of the reason for nonrenewal. Such notification shall be given the insured within twenty days after receipt of such request.