N.D. Cent. Code § 26.1-36.4-04

An insurer shall reduce any time period applicable to a pre-existing condition, for a policy by the aggregate of periods the individual was covered by qualifying previous coverage, if the qualifying previous coverage as defined in section 26.1-36.3-01 is continuous until at least sixty-three days before the effective date of the new coverage. Any waiting period applicable to an individual for coverage under a health benefit plan may not be taken into account in determining the period of continuous coverage. Insurers shall credit coverage in the same manner as provided by section 26.1-36.3-06 and the rules adopted by the commissioner pursuant thereto.