42 CFR § 406.34 - Determination of months to be counted for premium increase: Reenrollment.
(a) First reenrollment before April 1, 1981 or after September 30, 1981 and before January 1, 2023. The months to be counted for premium increase are:
(1) The months specified in § 406.33(a) or (b); plus
(2) The months from the end of the first period of entitlement through the end of the general enrollment period in which the individual reenrolled.
(b) First reenrollment during the period April 1, 1981 through September 30, 1981. The months to be counted for premium increase are—
(1) The months specified in § 406.33(a); plus
(2) The months from the end of the first period of entitlement through the month in which the individual reenrolled.
(c) Subsequent reenrollment during the period April 1, 1981 through September 30, 1981. The months to be counted for premium increase are—
(1) The months specified in paragraph (a) of this section; plus
(2) The months from April 1981 through the month in which the individual reenrolled for the second time. (Since only one reenrollment was permitted before April 1981, any months from the end of the individual's first enrollment period of entitlement through March 1981 are not counted.)
(d) Subsequent reenrollment after September 30, 1981. The months to be counted for premium increase are—
(1) The months specified in paragraph (a) or (b) of this section, for the first and second periods of coverage; plus
(2) The months from the end of each subsequent period of entitlement through the end of the general enrollment period in which the individual reenrolled, excluding any months before April 1981.
(e) Reenrollments on or after January 1, 2023.
(1) The months to be counted for premium increase are as follows:
(i) The months specified in § 406.33(c).
(ii) The months specified in paragraphs (b) and (d) of this section (if applicable).
(iii) The months from the end of the first period of entitlement through the end of the month during the general enrollment period in which the individual reenrolled.
(2) The months excluded from premium increase are the months of non-coverage in accordance with an individual's use of an exceptional conditions SEP under § 406.27, provided the individual enrolls within the duration of the SEP.
(f) Example. Peter M enrolled during his initial enrollment period, terminated his first coverage period in August 1979 and reenrolled for the first time in January 1980. The 7 months to be counted (September 1979 through March, 1980) were not enough to require any increase in the premium. Peter terminated his second period of coverage in February 1981 and reenrolled for the second time in July 1981. Since the 4 months (April through July 1981), when added to the previous 7 months, bring the total to only 11 months, no premium increase is required.