§ 2530.203-2 Vesting computation period.
(a) Designation of vesting computation periods. Except as provided in paragraph (b) of this section, a plan may designate any 12-consecutive-month period as the vesting computation period. The period so designated must apply equally to all participants. This requirement may be satisfied even though the actual 12-consecutive-month periods are not the same for all employees (e.g., if the designated vesting computation period is the 12-consecutive-month period beginning on an employee's employment commencement date and anniversaries of that date). The plan is prohibited, however, from using any period that would result in artificial postponement of vesting credit, such as a period meassured by anniversaries of the date four months following the employment commencement date.