N.D. Cent. Code § 26.1-40-03: Notice of cancellation

No insurer may exercise its right to cancel a policy unless a written notice of cancellation is mailed or delivered to the named insured, at the address shown in the policy, at least twenty days prior to the effective date of cancellation. When cancellation is for nonpayment of premium, the notice must be mailed or delivered to the named insured at the address shown in the policy at least ten days prior to the effective date of cancellation.