42 CFR § 408.8 - Grace period and termination date.
(a) Grace period.
(b) Extension of grace period: Last day is nonwork day. If the last day of the grace period is a Saturday, Sunday, legal holiday, or a day that, by statute or executive order, is a nonwork day for Federal employees, the grace period is extended to the next succeeding work day.
(d) Extension of grace period for good cause.
(1) CMS may reinstate entitlement, without interruption of coverage, if the individual shows good cause for failure to pay within the initial grace period, and pays all overdue premiums within three calendar months after the termination date.
(2) Good cause will be found if the individual establishes, by a credible statement, that failure to pay premiums within the initial grace period was due to conditions over which he or she had no control, or which he or she could not reasonably have been expected to foresee.
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