(1) A plan may designate 12-consecutive-month periods beginning on the first anniversary of an employee's employment commencement date and succeeding anniversaries thereof as the eligibility computation period after the initial eligibility computation period; or

(2) A plan may designate plan years beginning with the plan year which includes the first anniversary of an employee's employment commencement date as the eligibility computation period after the initial eligibility computation period (without regard to whether the employee is entitled to be credited with 1,000 hours of service during such period), provided that an employee who is credited with 1,000 hours of service in both the initial eligibility computation period and the plan year which includes the first anniversary of the employee's employment commencement date is credited with two years of service for purposes of eligibility to participate.

(1) A plan may use an initial eligibility computation period (or initial computation period for measuring completion of a year of service upon an employee's return after a one-year break in service) beginning on the first day of a period of no more than 31 days during which an employee's employment commencement date (or reemployment commencement date) occurs and ending on the anniversary of the last day of such period.

(2) If a plan uses an initial eligibility computation period (or initial computation period for measuring completion of a year of service upon an employee's return after a one-year break in service) permitted under paragraph (e)(1) of this section, the plan shall use the following computation periods after the initial computation period:

(3) For purposes of determining an employee's commencement of participation under section 202(a)(4) of the Act and section 410(a)(4) of the Code, regardless of whether an eligibility computation period permitted under this paragraph includes a period longer than 12 consecutive months, an employee who completes 1,000 hours of service in such eligibility computation period shall be treated as having satisfied the plan's service requirement for eligibility to participate as of the last day of the 12-consecutive-month period beginning on the first day of such eligibility computation period. In the case of a plan described in section 202(a)(1)(B)(i) of the Act and section 410(a)(1)(B)(i) of the Code, the requirement of the preceding sentence shall apply only with respect to the last year of service required under the plan for eligibility to participate.

(4) Example. A plan maintained by Employer X obtains records from X which indicate the number of hours worked by an employee during a monthly payroll period. The records do not, however, break down the number of hours worked by an employee by days. Thus, after a new employee has begun employment with X it is impossible for the plan to ascertain the employee's employment commencement date from the records furnished by X (although it is possible for the plan to determine the month during which an employee's employment commencement date occurred). For administrative convenience, in conjunction with the equivalency based on hours worked permitted under § 2530.200b-3(d)(1), and with the method of crediting hours of service to computation periods set forth in § 2530.200b-2(c)(4), the plan uses the alternative initial eligibility computation period permitted under this paragraph. The plan provides that an employee's initial eligibility computation period shall be the period beginning on the first day of the first monthly payroll period for which the employee is entitled to credit for the performance of duties and ending on the last day of the monthly payroll period which includes the anniversary of the last day of the initial monthly payroll period. This condition ensures that the initial eligibility computation period will include the 12-consecutive-month period beginning on the employee's employment commencement date and ending on the day before the anniversary of the employee's employment commencement date. If, however, an employee completes the plans requirement of one year of service for eligibility to participate (i.e., completion of 870 hours worked in an eligibility computation period) in the initial eligibility computation period, the plan provides that the employee is deemed to have satisfied the plan's service requirements for eligibility to participate as of the day before the anniversary of the first day of the initial eligibility computation period. This provision ensures that no employee who has in fact completed 1000 hours of service in the 12-consecutive-month period beginning on the employee's employment commencement date will be admitted to participation later than the date specified under section 202(a)(4) of the Act and section 410(a)(4) of the Code. For example, in the case of an employee who begins employment in January 1977, the employee's initial eligibility computation period begins on January 1, 1977 and ends on January 31, 1978. If the employee completes 879 hours worked in the initial eligibility computation period, the employee is treated as having met the plan's service requirements for eligibility to participate as of December 31, 1977. If the plan provides for semi-annual entry dates of January 1 and July 1, and the employee has met any eligibility requirements of the plan other than the minimum service requirement as of December 31, 1977, the plan must provide that the employee commences participation as of January 1, 1978.